HK1165660A - Plasma electric generation system - Google Patents

Description

Plasma power generation system

The present application is a divisional application entitled "plasma power generation system" with application number 200680007428.2, application date 2006, 3/7.

Technical Field

The present invention relates generally to the field of plasma physics and, more particularly, to methods and apparatus for confining plasma to enable nuclear fusion energy and for converting energy from fusion products into electrical energy.

Background

Fusion is the process of combining two light nuclei to form one heavier nucleus. The fusion process releases tremendous energy in the form of fast moving particles. Because the nuclei are positively charged-due to the protons contained therein-there is a repulsive electrostatic, i.e. coulomb, force between them. This repulsive force barrier must be overcome for two fused nuclei. This occurs when the two nuclei are sufficiently close together, at which time the short distance nuclear forces become strong enough to overcome the coulomb force and fuse the nuclei. The energy required for the nuclei to overcome the coulomb barrier is provided by their thermal energy, which must be very high. For example, if the temperature is at least 10 deg.C⁴ Of the order of eV-roughly corresponding to 10⁸The fusion rate can be considerable at kelvin temperature. The rate of fusion reactions is a function of temperature and is characterized by a quantity called the reaction rate. For example, the reactivity of the D-T reaction has a broad peak between 30 keV and 100 keV.

Typical fusion reactions include:

wherein D represents deuterium; t represents tritium; represents a helium nucleus; n represents a neutron; p represents a proton; he represents helium; b is¹¹Represents boron-11. The numbers in parentheses in each equation represent the kinetic energy of the fusion products.

The first two reactions listed above, the D-D and D-T reactions, are neutronic, meaning that most of the energy of the fusion products is carried by fast neutrons. The disadvantages of neutron reactions are: (1) fast neutron flux creates a number of problems, including structural damage to the reactor wall and high levels of radioactivity for most materials of manufacture; and (2) harvesting the fast neutrons' energy by converting their thermal energy into electrical energy, which is very inefficient (less than 30%). The advantages of neutron reaction are: (1) their reactivity peaks at relatively low temperatures; and (2) their losses due to radiation are relatively low, since the atomic number of deuterium and tritium is 1.

reaction-D-He in the other two equations³And p-B¹¹-known as premium fuel. Rather than producing fast neutrons as in neutron reactions, their fusion products are charged particles. One advantage of high-grade fuels is that they produce far fewer neutrons and therefore have fewer disadvantages associated with them. In D-He³Some fast neutrons are produced by secondary reactions, but these neutrons account for only about ten percent of the fusion product energy. p-B¹¹The reaction is fast neutron free, although it does produce some slow neutrons caused by secondary reactions, but produces far fewer problems. Another advantage of advanced fuels is that their fusion products include charged particles whose kinetic energy can be directly converted into electrical energy. With a suitable energy conversion process, the energy of the high-grade fuel fusion products can be collected with high efficiency, possibly in excess of ninety percent.

Higher grade fuels also have disadvantages. For example, the atomic number of advanced fuels is higher (for He)³Is 2, and for B¹¹Is 5). Therefore, their radiation losses are greater than in neutron reactions. Also, it is much more difficult to fuse higher fuels. Their peak reaction rates occur at much higher temperatures and are not as high as the reaction rates of D-T. Thus, the fusion reaction with high-grade fuels requires: bringing them to a higher energy state where their reactivity is very high. Therefore, the high-grade fuels must be closed (fusion) for an extended period of time during which they can reach the proper fusion conditions.

The closing time for the plasma isWherein r is the minimum plasma dimension and D is the diffusion coefficient. The classical value of the diffusion coefficient isWherein, in the step (A),is the radius of gyration of the ion, anIs the ion-electron collision time. Diffusion according to the classical diffusion coefficient is called classical migration. Bohm diffusion coefficient due to short wavelength instability isWhereinIs the ion gyration frequency. Diffusion according to this relationship is called anomalous migration. With respect to the conditions of fusion, it is preferred,10⁸abnormal migration results in a much shorter confinement time than classical migration. This relationship determines how large a plasma must be in a fusion reactor, with the requirement that the confinement time for a given amount of plasma must be longer than the time for the plasma nuclear fusion reaction. Therefore, classical migration conditions are more desirable in fusion reactors in view of the smaller initial plasma.

In early experiments with plasma toroidal confinement, it was observedThe sealing time of (c). The recent 40 years of progress has increased the closure time to. One existing fusion reactor concept is tokamak (Tokamat). Fusion in the past 30 yearsEfforts have focused on tokamak reactors utilizing D-T fuels. These efforts peak in the International Thermonuclear Experimental Reactor (ITER). Recently, the classical migration was proposed in the context of tokamak experimentsIt is possible that in the case of classical migration, the minimum plasma size can be reduced from meters to cm. These experiments involve the implantation of a high energy beam (50 to 100 keV) and heating the plasma to a temperature of 10 to 30 keV. See w.heidbrink and g.j.sadler, 34 Nuclear Fusion 535 (1984). It was observed in these experiments that high-energy beam ions slowed down and classically diffused as the thermal plasma continued to diffuse abnormally fast. The reason for this is that high-energy beam ions have a large radius of gyration and, therefore, for wavelengths shorter than the ion radius of gyration: () Is insensitive to fluctuations in. Short wavelength fluctuations will average out the period and thus cancel. However, electrons have much smaller radii of gyration, so they respond abnormally to fluctuations and migration.

The minimum size of the plasma must be at least 2.8 meters because of anomalous migration. Due to this size, ITERs were built 30 meters high and 30 meters in diameter. This is the smallest possible D-T tokamak type reactor in practice. For higher fuels, e.g. D-He³And p-B¹¹The tokamak type reactor would have to be much larger because the fuel ions have a much longer time to react with the nuclei. There is an additional problem with tokamak type reactors using D-T fuel in that most of the energy of the fusion product energy is carried by 14 MeV neutrons, which in almost all materials of construction cause radiation damage and induce reactivity due to neutron flux. In addition, their energy conversion to electrical energy must be by a thermal process, so that the conversion efficiency is not more than 30%.

Another proposed reactor configuration is a collisional beam reactor. In a collision beam reactor, the background plasma is bombarded by some ion beam. These beams contain ions having a much larger energy than thermal plasmas. It has not been practical to produce useful fusion reactions in this type of reactor because the background plasma slows down the ion beam. To reduce this problem and to maximize the number of nuclear reactions, various proposals have been made.

For example, U.S. patent No.4065351 to Jassby et al discloses a method of generating a countercurrent collision beam of deuterium and tritium in an annular confinement system. In U.S. patent No.4057462 to Jassby et al, the injection of electromagnetic energy counteracts the effect of the bulk-balanced plasma drag on one of these ion species. The annular restraint system is equivalent to tokamak. In U.S. patent No.4894199 to rotoker, deuterium and tritium are injected and trapped in a tokamak mirror, i.e., field reversed configuration, with the same average velocity. There is a low density of cold background plasma for the sole purpose of trapping the beam. The beams react because they have high temperatures and are slowed primarily by electrons that accompany the implanted ions. The electrons are heated by the ions, in which case there is minimal slowing down.

However, the balancing electric field does not play any role in any of these devices. Furthermore, there is no intention to reduce or even take into account abnormal migration.

Other patents consider electrostatic confinement of ions and in some cases magnetic confinement of electrons. These patents include Farnsworth U.S. patent No.3258402 and Farnsworth U.S. patent No.3386883 (which disclose electrostatic confinement of ions and inertial confinement of electrons), Hirsch et al U.S. patent No.3530036 and Hirsch et al U.S. patent No. 3530497 (similar to Farnsworth), limmacer U.S. patent No.4233537 (which discloses electrostatic confinement of ions and magnetic confinement of electrons with multipole cusps to cut reflective walls), and buslard U.S. patent No.4826646 (similar to limmacer and containing point cusps). None of these patents consider electrostatic confinement of electrons and magnetic confinement of ions. While there have been many research topics relating to electrostatic confinement of ions, none of them has succeeded in establishing the required electrostatic field when the ions have the density required by a fusion reactor. Finally, none of those patents cited above discuss field-reversed configuration magnetic topologies.

Occasionally field reversal deployment (FRC) occurred during azimuthal pinching (theta ping) experiments in the naval research laboratory in about 1960. Fig. 3 and 5 illustrate a typical FRC topology where the internal magnetic field reverses direction, while fig. 6 and 9 show the particle trajectories in the FRC. With respect to FRC, many research programs have been funded in the united states and japan. There is a general review of the theory and experiments on FRC studies from 1960 to 1988. See m.tusewski, 28 Nuclear Fusion 2023 (1988). A white paper on FRC development describes the studies in 1996 and recommendations for future studies. See l.c. steinhauer et al, 30 fusion technology 116 (1996). To date, in FRC experiments, FRCs were formed using an azimuthal pinching method. The consequence of this formation method is that the ions and electrons each carry half the current, which results in negligible and no electrostatic field confinement in the plasma. Ions and electrons in these FRCs are magnetically confined. Abnormal migration was assumed in almost all FRC experiments. See, for example, the Tusewski paper at the beginning of section 1.5.2, 2072.

Accordingly, it is desirable to provide a fusion system having a closed system that will significantly reduce or eliminate anomalous migration of ions and electrons and an energy conversion system that converts the energy of the fusion products into electrical energy with high efficiency.

Disclosure of Invention

The present invention relates to a system that facilitates controlled fusion in a magnetic field having a field reversal topology and the conversion of fusion product energy to electrical power. The system, referred to herein as a plasma power generation (PEG) system, preferably comprises a fusion reactor having a closed system that tends to significantly reduce or eliminate anomalous migration of ions and electrons. Additionally, PEG systems also include reactor-coupled energy conversion systems that directly convert fusion product energy into electrical energy at high efficiency.

In one embodiment, anomalous migration of both ions and electrons is substantially reduced or eliminated. Anomalous migration of ions is avoided by magnetically confining the ions in a magnetic field in a Field Reversed Configuration (FRC). For electrons, the tuning of the applied magnetic field generates a strong electric field that electrostatically confines the electrons in a deep potential well, avoiding anomalous migration of energy. As a result, the fusion fuel plasma that can be used in the present confinement apparatus and process is not limited to neutron fuel, but advantageously includes advanced, i.e., non-neutron, fuels as well. For non-neutron fuels, the fusion reaction energy is almost entirely in the form of charged particles, i.e., energetic ions. These charged particles can be manipulated in a magnetic field, depending on the fuel, causing little or no radioactivity.

In a preferred embodiment, a plasma confinement system of a fusion reactor comprises a chamber, a magnetic field generator for applying a magnetic field in a direction substantially along a major axis, and a toroidal plasma layer comprising an circulating ion beam. The torroidal plasma beam layer is substantially magnetically confined within the chamber in the form of an orbit, while the electrons are substantially retained in the electrostatic energy trap. In a preferred embodiment, the magnetic field generator comprises a current coil. Preferably, the magnetic field generator further comprises mirror coils (mirror coils) near the chamber ends, which increase the amplitude of the externally applied magnetic field at the chamber ends. The system also includes one or more beam implanters for implanting the neutralized ion beam into the magnetic field. In the magnetic field, the beam enters the track due to the force generated by the magnetic field. In a preferred embodiment, the system forms a magnetic field having a topology of field reversal configurations.

In another preferred embodiment, an optional chamber is provided that prevents azimuthal mirror currents from forming in the central region of the chamber walls and allows magnetic flux to pass through the chamber quickly. A chamber consisting essentially of stainless steel, which provides structural strength and good vacuum performance, includes axial insulation breaks (breaks) in the chamber wall extending along almost the entire chamber length. Preferably, there are 3 interruptions spaced about 120 degrees apart from each other. These interruptions include slots or gaps formed in the wall. An insert comprising an insulating material, preferably ceramic or the like, is inserted into the slot or slit. Inside the chamber, a metal cover covers the insert. Outside the chamber, the insert is attached to a sealing plate, preferably formed of fiberglass or the like. The seal plate forms a vacuum barrier with the stainless steel surface of the chamber wall by means of an O-ring seal.

In yet another preferred embodiment, the induction plasma source is chamber mountable and includes a briberbed assembly (preferably a single turn briberbed). It is preferably fed by a high voltage (about 5-15 kV) power supply (not shown). Neutral gases such as hydrogen (or other suitable gaseous fusion fuel) are introduced into the source by direct gas feed through a Laval (Laval) nozzle. Once the gas exits the nozzle and distributes itself over the coil winding surfaces of the briberbed, the windings are energized. The ultrafast current and flux jump in the low inductance briberband results in a very high electric field within the gas. The electric field causes the breakdown, ionization, and plasma formed to be subsequently ejected from the briberbed surface toward the center or mid-plane of the chamber.

In yet another preferred embodiment, the RF drive comprises a quadrupole cyclotron within the chamber having 4 azimuthally symmetric electrodes with a gap between them. Quadrupole cyclotrons produce a potential wave that rotates in the same direction as the azimuthal velocity of the ions but at a greater velocity. Ions of appropriate velocity can be trapped in this wave and periodically reflected. This process increases the momentum and energy of the fuel ions, and this increase is transferred to the fuel ions that are not trapped by collisions.

In another embodiment, a direct energy conversion system is used to convert the kinetic energy of fusion products directly into electricity by slowing charged particles through an electromagnetic field. Advantageously, the direct energy conversion system of the present invention has efficiency, particle energy tolerance and electronic capability to convert the frequency and phase of the fusion output power of about 5 MHz to match the frequency of the external 60 Hz grid.

In a preferred embodiment, the energy conversion system comprises an Inverse Cyclotron Converter (ICC) coupled to an opposite end of the fusion reactor. The ICC has a hollow cylindrical geometry consisting of a plurality of (preferably 4 or more) equal semi-cylindrical electrodes with small straight gaps extending between them. In operation, an oscillating potential is applied to the electrodes in an alternating manner. The electric field E within the ICC has a multipole structure, vanishing on the axis of symmetry, increasing linearly with radius, with a peak at the slot.

In addition, the ICC includes a magnetic field generator for applying a uniform unidirectional magnetic field in a direction substantially opposite to the externally applied magnetic field of the closed system of the fusion reactor. At the furthest end from the fusion reactor power core, the ICC includes an ion collector. Between the power core and the ICC is a symmetric magnetic cusp where the magnetic field of the closed system merges with the magnetic field of the ICC. An annular electron collector is disposed about the magnetic cusp and coupled to the ion collector.

In yet another preferred embodiment, the product nuclei and charge neutralizing electrons emerge from both ends of the reactor power core as annular beams at a density at which the magnetic cusps separate the electrons and ions due to their energy differences. The electrons follow the magnetic field lines to the electron collector and the ions pass through the magnetic cusp where the ion trajectory changes to a substantially helical path along the length of the ICC. As the ion spirals pass through the electrodes connected to the resonant circuit, energy is removed from them. The loss of vertical energy is greatest for the highest energy ions that initially circulate near the electrode where the electric field is strongest.

Other aspects and features of the present invention will become apparent from the following description considered in conjunction with the accompanying drawings.

Drawings

Some preferred embodiments are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings. Like reference numerals in the drawings refer to like elements.

FIG. 1 shows a partial view of an exemplary confinement chamber.

FIG. 2A illustrates a partial view of another exemplary confinement chamber.

Fig. 2B shows a partial cross-sectional view along line 2B-2B of fig. 2A.

Fig. 2C shows a detailed view along line 2C on fig. 2B.

Fig. 2D shows a partial cross-sectional view along line 2D-2D on fig. 2B.

Fig. 3 shows the magnetic field of the FRC.

Fig. 4A and 4B show diamagnetic and diamagnetic directions, respectively, in an FRC.

Fig. 5 shows a collision beam system.

Figure 6 shows an electromagnetic induction accelerator track.

Fig. 7A and 7B show the direction of magnetic field and gradient drift, respectively, in an FRC.

FIGS. 8A and 8B show the electric field in FRC andthe direction of the drift.

Fig. 9A, 9B, and 9C show ion drift trajectories.

Fig. 10A and 10B show the lorentz forces at the end of the FRC.

Fig. 11A and 11B show tuning of electric fields and potentials in an oscillating beam system.

Fig. 12 shows maxwell distribution.

Fig. 13A and 13B illustrate the transition from the electromagnetic induction accelerator orbit to the drift orbit due to large angle ion-ion collisions.

Figure 14 shows A, B, C and D betatron trajectories when small angle electron-ion collisions are considered.

Fig. 15 shows a neutral ion beam when electrically polarized.

Fig. 16 shows a front view of a neutral ion beam as it contacts plasma in a confinement chamber.

FIG. 17 is a schematic end view of a confinement chamber according to a preferred embodiment of the start-up process.

FIG. 18 is a schematic end view of a confinement chamber according to another preferred embodiment of the start-up process.

Fig. 19 shows traces of B-shaped point detection indicating FRC formation.

Fig. 20A shows a view of an inductive plasma source that may be installed in a chamber.

Fig. 20B and 20C show partial views of an inductive plasma source.

Fig. 21A and 21B show partial views of the RF drive system.

Figure 21C shows a schematic of a dipole and quadrupole configuration.

Fig. 22A shows a portion of a plasma power generation system including a collision beam fusion reactor in combination with an inverse cyclotron direct energy converter.

Figure 22B shows an end view of the reverse cyclotron converter of figure 19.

Fig. 22C shows the trajectories of ions in the reverse cyclotron.

Fig. 23A shows a portion of a plasma power generation system including a collision beam fusion reactor in combination with an alternative embodiment of an inverse cyclotron converter.

Figure 23B shows an end view of the reverse cyclotron converter on figure 20A.

Fig. 24A shows a particle orbit in a conventional cyclotron.

FIG. 24B shows an oscillating electric field.

Fig. 24C shows the change energy of the accelerated particles.

Fig. 25 shows the azimuthal electric field at the gap between the electrodes of the ICC, which is experienced by ions with angular velocity.

Fig. 26 shows a focusing quadrupole doublet.

Fig. 27A and 27B show an auxiliary magnetic field coil system.

Figure 28 shows a 100 MW reactor.

Fig. 29 shows a reactor support apparatus.

FIG. 30 shows a plasma thrust propulsion system.

Fig. 31 shows main components of the plasma thruster propulsion system.

Fig. 32 shows a block diagram of a plasma thruster propulsion system.

Detailed Description

As illustrated in the figures, the plasma power generation (PEG) system of the present invention preferably includes a Collision Beam Fusion Reactor (CBFR) coupled to a direct energy conversion system. As indicated above, ideal fusion reactors solve the problem of abnormal migration of both ions and electrons. The approach to solving the anomalous migration problem found here utilizes a closed system with a magnetic field having a Field Reversed Configuration (FRC). In this way, most ions have large non-adiabatic orbits, making them insensitive to short wavelength fluctuations that cause anomalous migration of adiabatic ions, which is avoided by magnetic field confinement in the FRC. In particular, the FRC has a region where the magnetic field disappears, making it possible to have a plasma including a large number of non-adiabatic ions. For electrons, anomalous migration of energy is avoided by tuning the applied magnetic field to create a strong electric field. The strong electric field electrostatically confines the electrons in a deep potential well.

Can be used as a notebookFusion fuel plasma used with confinement apparatus and processes is not limited to neutron fuels such as D-D (deuterium-deuterium) or D-T (deuterium-tritium), but advantageously also includes neutron fuels such as D-He³(deuterium-helium-3) or p-B¹¹(hydrogen-boron-11) such advanced or non-neutron fuels. (for a discussion of advanced fuels, see R. Feldbacher and M. Heinder, Nuclear Instruments and Method, Physics Research, A271 (1988) jj-64 (Amsterdam, North Netherlands)). For such non-neutron fuels, the fusion reaction energy is almost entirely in the form of charged particles, i.e., energetic ions. These charged particles can be manipulated in a magnetic field and, depending on the fuel, cause little radioactivity. D-He³The reaction produces an H ion and He with an energy of 18.2 MeV⁴Ion, and p-B¹¹Reaction producing 3 He⁴Ions and 8.7 MeV energy. For example, according to theoretical modeling for fusion devices utilizing non-neutron fuels, the output energy conversion efficiency can be as high as about 90%, as described in k.yoshikawa, k.noma, and y.yamamoto in fusion technology, 19, 870 (1991). Such efficiency significantly enhances the promise of non-neutron fuels in scalable (1-1000 MW), small, low cost configurations.

The charged particles of fusion products can be slowed down in the direct energy conversion process of the present invention and their kinetic energy can be directly converted into electrical energy. Advantageously, the direct energy conversion system of the present invention has the efficiency, particle energy tolerance and electronic capability to convert the frequency and phase of the fusion output power of about 5 MHz to match the frequency and phase of the external 60 Hz grid.

Fusion enclosure system

Fig. 1 illustrates a preferred embodiment of a closure system 300 according to the present invention. The enclosure system 300 includes a chamber wall 305 in which a confinement chamber 310 is defined. Preferably, the confinement chamber 310 is cylindrical in shape, having a major axis 315 along the center of the chamber 310. In order to apply the containment system 300 to a fusion reactor, it is necessary to establish a vacuum or near vacuum within the chamber 310. Concentric to the main axis 315 is an electromagnetic induction accelerator flux coil (flux coil) 320, located within the chamber 310. The electromagnetic induction accelerator flux coil 320 comprises a current carrying medium adapted to conduct current around the long coil, as shown, the medium preferably comprising a parallel winding of a plurality of individual coils, most preferably a parallel winding of about 4 individual coils, to form the long coil. Those skilled in the art will appreciate that current passing through the betatron coil 320 will generate a magnetic field in the betatron coil 320 that is substantially in the direction of the principal axis 315.

Surrounding the outside of the chamber wall 305 is an outer coil 325. The external coil 325 generates a relatively constant magnetic field having a magnetic flux substantially parallel to the main axis 315. The magnetic field is azimuthally symmetric. The magnetic field induced by the outer coil 325 is constant and parallel to the main axis 315, with the most accurate away from the end of the chamber 310. At each end of the chamber 310 is a mirror coil 330. The mirror coils 330 are adapted to generate an increasing magnetic field in the chamber 310 at each end, thus bending the flux lines inward at each end (see fig. 3 and 5). As explained, this inward bending of the magnetic field lines helps to confine plasma 335 within the enclosure within chamber 310, generally between mirror coils 330, by pushing it away from the end where it would escape enclosure system 300. The mirror coil 330 housing is adapted to generate an increased magnetic field at the ends by various methods known in the art, including increasing the number of windings in the mirror coil 330, increasing the current through the mirror coil 330, or overlapping the mirror coil 330 with an external coil 325.

The external coil 325 and the mirror coil 330 as shown in FIG. 1 are implemented outside the chamber wall 305; however, they may also be inside the chamber 310. In the case where the chamber wall 305 is constructed of a conductive material, such as a metal, it is advantageous to place the coils 325, 330 inside the chamber wall 305 because the time it takes for the magnetic field to diffuse through the wall 305 can be relatively large, thus making the system 300 slow to react. Similarly, the chamber 310 may be in the shape of a hollow cylinder with the chamber walls 305 forming a long, annular ring. In such a case, the electromagnetic induction accelerator flux coil 320 may be implemented outside the chamber wall 305 at the center of this annular ring. Preferably, the inner wall forming the center of the annular ring may comprise a non-conductive material such as glass. As will become apparent, the chamber 310 must be of a size and shape sufficient to allow the circulating plasma beam or layer 335 to rotate about the main axis 315 with a radius.

The chamber wall 305 may be formed from a material having a high magnetic permeability, such as steel. In such a case, the chamber walls 305 help keep the magnetic flux from escaping the chamber 310, "compressing" it due to the reverse currents induced in the material. If the chamber walls are made of a material with low magnetic permeability, such as plexiglass, another means for enclosing the magnetic flux would be necessary. In such a case, a series of closed loop, flat metal rings may be provided. These rings, referred to in the art as flux limiters, will be provided inside the external coil 325, but outside the circulating plasma beam 335. Further, these flux limiters may be passive or active, wherein active limiters are driven with a predetermined current to further facilitate the enclosure of the magnetic flux within the chamber 310. Alternatively, the external coils 325 themselves may be used as flux limiters.

As explained in more detail below, the circulating plasma beam 335 containing charged particles may be enclosed within the chamber 310 by lorentz forces caused by the magnetic field induced by the external coil 325. As such, ions in the plasma beam 335 are magnetically confined on a large electromagnetic induction accelerator orbit around the magnetic flux lines from the outer coil 325, which are parallel to the major axis 315. One or more beam injection ports 340 are also provided in the chamber 310 for adding plasma ions to the circulating plasma beam 335. In a preferred embodiment, the implantation ports 340 are adapted to implant the ion beam at about the same radial location from the major axis 315 at which the circulating plasma beam 335 is enclosed (i.e., around a null plane as described below). In addition, the implantation port 340 is adapted to be tangential to and implant an ion beam 350 in the direction of the electromagnetic induction accelerator trajectory of the confined plasma beam 335 (see fig. 17).

One or more background plasma sources 345 are also provided for implanting the non-energetic plasma cloud into the chamber 310. In a preferred embodiment, the background plasma source 345 is adapted to direct the plasma 335 toward the axial center of the chamber 310. It has been found that directing the plasma in this manner helps to better confine plasma 335 and results in a high density of plasma 335 within the confinement region within chamber 310.

Vacuum chamber

As mentioned above, for the application of a closed system of CBFR, it is necessary to create a vacuum or near vacuum inside the chamber. Since the interaction between neutrals and plasma fuel (scattering, charge exchange) always provides an energy loss path, it is critical to limit the residue density within the reactor chamber. In addition, impurities resulting from a poorly evacuated chamber can lead to contamination side reactions during operation and can consume excessive energy during start-up as the system has to burn off these residues.

Achieving a good level of vacuum typically involves the use of stainless steel chambers and ports and low outgassing materials. In the case of metals, good vacuum performance is further coupled with good structural properties. However, conductive materials such as stainless steel present various problems with respect to their electrical properties. While these negative effects are all linked, they manifest themselves in different ways. Among the most negative characteristics are: the decelerated diffusion of the magnetic field through the chamber walls, the accumulation of charge on the surface, the sharp change in the response time of the system to transient signals, and the formation of image currents on the surface that affect the desired magnetic topology. Materials that do not have these undesirable characteristics and exhibit good vacuum performance are insulators such as ceramics, glass, quartz and to a lesser extent carbon fibers. The main problems with these materials are structural integrity and the possibility of accidental damage. Manufacturing problems such as poor processability of the ceramic are additional limitations.

In one embodiment, as depicted on fig. 2A, 2B, 2C, and 2D, an alternative chamber 1310 is provided that minimizes these problems. The chamber 1310 of the CBFR is preferably constructed primarily of metal (preferably stainless steel, etc.) to provide structural strength and good vacuum performance. However, the cylindrical wall 1311 of the chamber 1310 includes an axial insulating discontinuity 1360 in the wall 1311 that extends along almost the entire length of the chamber 1310 in a central portion of the chamber 1310, or power core region of the CBFR. Preferably, as depicted in FIG. 2B, there are 3 interruptions 1360 spaced about 120 degrees apart from each other. As depicted on fig. 2C, the discontinuity 1360 includes a slot or gap 1362 in the wall 1311 of the chamber 1310, with a sealing slot or seat 1369 formed around the edge of the slot 1362. An O-ring seal 1367 is received in the groove 1369. As depicted on fig. 2D, the slots 1362 extend the entire length of the chamber 1310, with enough stainless steel material to form an azimuthally continuous portion of the walls 1311 near both ends to provide structural integrity and to provide for a good quality vacuum seal at the ends. To improve structural integrity and prevent implosion, as depicted on FIG. 2A, the chamber 1310 preferably includes a plurality of sets of locally oriented ribs 1370 that are integrally formed with the chamber wall 1311 or are bonded to the surface of the chamber wall 1311 by welding or the like.

As depicted on fig. 2C, the gap 1362 is filled with an insert 1364 formed of a ceramic material. The insert 1364 protrudes slightly into the interior of the chamber 1310 and is covered on the inside by a metal cover 1366 to prevent secondary plasma emission from the circulating plasma beam from colliding with the ceramic. Outside of chamber 1310, insert 1364 is attached to seal plate 1365, which forms a vacuum barrier with the stainless steel surface of chamber wall 1311 by means of O-ring seal 1367. To maintain the desired vacuum performance, the seal plate 1365 is preferably constructed of a substrate (preferably fiberglass or the like) that is flexible and forms a tighter seal with the O-ring 1367 than ceramic material, particularly when the chamber 1310 is slightly deformed by inward pressure.

Inserts or ceramic insulators 1364 within slots 1362 preferably prevent current from arcing across slot 1362 and thereby prevent azimuthal image currents from forming in chamber wall 1311. As described below, the mirror current is a lenz's law phenomenon, which is a natural tendency to resist any magnetic flux changes: such as the magnetic flux changes that occur in the flux coil 1320 during the formation of CBFR. If there is no slot 1362 in the cylindrical wall 1311 of the chamber 1310, the changing magnetic flux in the flux coil 1320 causes an equal but opposite induced current to form in the stainless steel wall 1311 to cancel the magnetic flux change inside the chamber 1310. While the induced image current may be weaker than the current applied to the flux coil 1320, the image current tends to strongly reduce the applied or confinement magnetic field within the chamber 1310, which when unresolved, tends to negatively affect the magnetic field topology and change the confinement characteristics within the chamber 1310. The presence of the slots 1362 prevents azimuthal image currents from forming in the chamber wall 1311 towards the mid-plane of the chamber 1310 away from the ends of the chamber 1310 in azimuthally continuous portions of the chamber wall 1311. The only image current that can be carried by the chamber wall 1311 toward the mid-plane away from the end of the chamber 1310 is a very weak current flowing parallel to the longitudinal axis of the slot 1362. Such currents have no effect on the axial magnetic confinement field of the FRC because the magnetic mirror field produced by the mirror currents passing longitudinally through the chamber wall 1311 only exhibits radial and azimuthal components. Azimuthal image currents formed in azimuthally continuous conductive portions of the wall 1311 near the ends of the chamber 1310 do not tend to negatively affect and/or alter confinement characteristics inside the chamber 1310, as the magnetic topology near that is not important to plasma confinement.

In addition to preventing azimuthal image currents from forming in the chamber wall 1311, the slots 1362 provide paths for magnetic flux to quickly penetrate the chamber 1310 from the field and image coils 1325 and 1330. As a result, slot 1362 enables sub-millisecond fine tuning and feedback control of the applied field.

Charged particles in FRC

Fig. 3 shows the magnetic field of the FRC 70. The system has cylindrical symmetry about its axis 78. In FRC, there are two areas of magnetic flux: open 80 and closed 82. The face separating these two regions is called the interface 84. The FRC forms a cylindrical null plane 86 on which the magnetic field disappears. In the central portion 88 of the FRC, the magnetic field does not change significantly in the axial direction. At end 90, the magnetic field does change significantly in the axial direction. In an FRC, the magnetic field along the central axis 78 reverses direction, which leads to the term "reversed" in a Field Reversed Configuration (FRC).

In fig. 4A, the magnetic field outside the null plane 94 is in a first direction 96. The magnetic field within the null plane 94 is in a second direction 98 opposite the first direction. If an ion moves in the direction 100, the Lorentz force 30 acting on it is directed toward the null plane 94. This situation is easily understood by applying the right hand rule. For particles moving in the diamagnetic direction 102, the lorentz force is always directed at the null plane 94. This phenomenon results in a particle orbit called the electromagnetic induction accelerator orbit, which will be described below.

Figure 4B shows an ion moving in the diamagnetic direction 104. The lorentz force in this case is directed away from the null plane 94. This phenomenon results in a type of track, called a drift track, to be described below. The diamagnetic direction of an ion is the diamagnetic direction of an electron, and vice versa.

Fig. 5 shows a plasma torus or torus layer 106 rotating in the diamagnetic direction of the ions. The ring 106 is positioned around the zero plane 86. The magnetic field 108 generated by the toroidal plasma layer 106 joins with the applied magnetic field 110 to form a magnetic field having a topology of FRCs (the topology is shown in fig. 3).

The ion beam forming the plasma layer 106 has a temperature, and thus the velocities of these ions form a maxwell distribution in a frame that rotates at the average angular velocity of the ion beam. Collisions between ions of different velocities result in fusion reactions. For this reason, the plasma beam layer or power core 106 is referred to as a collision beam system.

Figure 6 shows the main type of ion trajectory in a collision beam system called an electromagnetic induction accelerator trajectory 112. The electromagnetic induction accelerator track 112 can be represented as a sine wave centered on the null circle 114. As explained above, the magnetic field on the null circle 114 disappears. The plane of the rail 112 is perpendicular to the axis 78 of the FRC. Ions on this trajectory move in their diamagnetic direction 102 from the origin 116. Ions on the orbit of an electromagnetic induction accelerator have two motions: vibration in the radial direction (perpendicular to the null circle 114) and translation along the null circle 114.

Fig. 7A is a diagram of the magnetic field 118 in an FRC. The horizontal axis of the graph represents distance in cm from the FRC axis 78. The magnetic field is in units of thousand gauss. As depicted in this figure, the magnetic field 118 becomes zero at the null circle radius 120.

As shown on fig. 7B, a particle moving near the null circle will experience a magnetic field gradient 126 directed away from the null plane 86. The magnetic field outside the null circle is in a first direction 122 and the magnetic field inside the null circle is in a second direction 124 opposite the first direction. The direction of gradient drift is defined by cross productIt is given that, here,is a magnetic field gradient; thus, by applying right-hand rules, it can be understood that the direction of gradient drift is in the diamagnetic direction, whether the ions are outside or inside the null circle 128.

Fig. 8A is a diagram of the electric field 130 in the FRC. The horizontal axis of the graph represents distance in cm from the FRC axis 78. The electric field is in volts/cm. As depicted in this figure, the electric field 130 becomes zero near the zero-bit circle radius 120.

As shown in fig. 8B, the electric field is unconfined (deconfining) for ions that point in directions 132, 134 away from the zero plane 86. As before, the magnetic fields are in opposite directions 122, 124, both inside and outside the null plane 86. As can be understood by applying the right-hand rule,the direction of drift is in the diamagnetic direction 102, whether the ions are outside or inside the zero plane 136.

Fig. 9A and 9B show another type of common track in an FRC called a drift track 138. The drift trajectory 138 can be outside the null plane 114, as shown in fig. 9A, or inside it,as shown on fig. 9B. If it is notThe drift trajectory 138 rotates in the diamagnetic direction if the drift dominates, or the drift trajectory 138 rotates in the diamagnetic direction if the gradient drift dominates. The drift track 138 shown in fig. 9A and 9B rotates from the starting point 116 in the diamagnetic direction 102.

As shown on fig. 9C, the drift trajectory can be thought of as a small circle rolling on a relatively large circle. The small circle 142 spins about its axis in the indicated direction 144. It also rolls in direction 102 over large circle 146. The point 140 will follow the same path in space as 138.

Fig. 10A and 10B show the direction of the lorentz force at the FRC end 151. In fig. 10A, ions are shown moving in a magnetic field 150 at a velocity 148 in a diamagnetic direction 102. As can be understood by applying right-hand rules, the lorentz force 152 tends to push the ions back into the closed field force line region. Therefore, in this case, the lorentz force 152 is binding to the ions. In fig. 10B, the ions are shown moving in a magnetic field 150 at a velocity 148 in an anti-magnetic direction. As can be understood by applying right-hand rules, the lorentz force 152 tends to push ions into the open field force line region. Therefore, in this case, the lorentz force 152 is unconfined for the ions.

Magnetic and electrostatic confinement in FRC

A plasma layer 106 (see fig. 5) can be formed in the FRC by implanting a high energy ion beam around the zero plane 86 in the diamagnetic direction 102 of the ions. (some different methods of forming FRC and plasma loops are discussed in detail below). In the circulating plasma layer 106, most of the ions have an electromagnetic induction accelerator track 112 (see fig. 6), are energetic, and are non-adiabatic. Therefore, they are insensitive to short wavelength fluctuations that cause anomalous migration.

In the plasma layer 106 formed under equilibrium conditions in FRC, conservation of momentum is at the angular velocity of the ionsAnd the angular velocity of the electronsTo apply a relationship therebetween. The relationship is

Wherein （1）

In the case of the equation 1, the,is the atomic number of the ion,is the mass of the ions, and,is the charge of the electron(s),is the magnitude of the applied magnetic field, andis the speed of light. There are 3 free parameters in this relationship: magnitude of externally applied magnetic fieldAngular velocity of electronsAnd the angular velocity of the ions. If two of them are known, the 3 rd can be determined from equation 1.

Since the plasma layer 106 is formed by implanting an ion beam into the FRC, the angular velocity of the ionsInjected kinetic energy from beamIt is determined that,is given by

Here, the first and second liquid crystal display panels are,whereinIs the implantation velocity of the ions and,is the cyclotron frequency of the ion, andis the radius of the zero plane 86. The kinetic energy of the electrons in the beam has been neglected because of the electron massSpecific ion massMuch smaller.

For a fixed beam implant velocity (fixed)) Capable of tuning an applied magnetic fieldSo as to be differentValues are available. Tuning the external magnetic field, as will be shownDifferent values of the electrostatic field within the plasma layer are also generated. The features of the present invention are illustrated in fig. 11A and 11B. FIG. 11A shows for the same implant rate (A)=1.35x10⁷s^-1) But for the value of the applied magnetic field3 different values of (a), 3 electric field (in volts/cm) curves obtained:

curve line	An external magnetic field of）	Angular velocity of electrons: (）
			154	=2.77 KG	=0
156	=5.15 KG	=0.625x107s-1
			158	=15.5 KG	=1.11x107s-1

In the above tableThe value is determined according to equation 1. It can be appreciated that, in equation 1,> 0 means＞Causing the electrons to rotate in their diamagnetic direction. FIG. 11B shows for the same groupValue sumPotential of value (in volts). The horizontal axis of fig. 11A and 11B represents the distance from the FRC axis 78, expressed in cm in the figure. The electric field and potential strongly depend on。

The above results can be interpreted on a simple physical basis. As the ions rotate in diamagnetic directions, the ions are magnetically constrained by the lorentz force. This is shown in fig. 4A. For electrons that rotate in the same direction as the ions, the lorentz force is in the opposite direction, so that the electrons are not confined. The electrons leave the plasma, resulting in a surplus of positive charge. This creates an electric field that prevents other electrons from leaving the plasma. The direction and magnitude of the electric field is determined by conservation of momentum at equilibrium.

This electrostatic field plays an important role in the migration of electrons and ions. Accordingly, it is an important aspect of the present invention that a strong electrostatic field is generated within the plasma layer 106, the magnitude of which is easily adjustable by an externally applied magnetic fieldThe value of (2) is controlled.

As explained, if> 0, the electrostatic field is electron-confining. As shown in fig. 11B, by tuning the applied magnetic fieldThe bit well depth can be increased. Electrons always have a small radius of gyration, except for the very narrow near zero circle region. Therefore, electrons respond to short wavelength fluctuations with exceptionally fast diffusivity. In fact, this diffusion helps to maintain the potential well once the fusion reaction occurs. Fusion product ions (of much higher energy) exit the plasma. To maintain charge quasi-neutrality, the fusion products must pull electrons out of the plasma along with them, primarily carrying electrons away from the plasma layer surface. The electron density at the plasma surface is low and the electrons leaving the plasma with the fusion products must be replaced or the potential well will disappear.

Figure 12 shows a maxwell velocity profile 162 of electrons. Only very high energy electrons from the maxwell distribution tail 160 reach the plasma surface and exit with the converging ions. The tail 160 of maxwell's distribution 162 is thus generated by electron-electron collisions in a high density region near the zero plane. These high energy electrons still have a small radius of gyration, such that anomalous diffusion allows them to reach the surface quickly enough to accommodate the exiting fusion product ions. These energetic electrons climb potential wells losing their energy and leave with little energy. Although electrons can rapidly cross the magnetic field due to abnormal migration, abnormal energy loss tends to be avoided because very little energy is migrated.

Another consequence of potential wells is a strong cooling mechanism for electrons similar to evaporative cooling. For example, for water to evaporate, it is necessary to supply it with latent heat of evaporation. This heat is supplied by the remaining liquid water and the surrounding medium, which then rapidly thermalizes to a lower temperature more quickly than the heat transfer process can replace the energy. Similarly, for electrons, the potential well depth is equal to the latent heat of evaporation of water. Through the thermalization process, which in turn supplies energy to the maxwell tail, the electrons supply the energy needed to climb the potential well so that the electrons can escape. Thus, the thermalization process results in a lower electron temperature because it is much faster than any heating process. Because of the mass difference between electrons and protons, the energy transfer time from protons is approximately one of about 1800 times the electron thermalization time. This cooling mechanism also reduces radiative losses of electrons. This is particularly important for premium fuels, where the radiative losses are enhanced by fuel ions having an atomic number Z greater than 1 (Z > 1).

The electrostatic field also affects ion transport. Most of the particle trajectories in the plasma layer 106 are electromagnetic induction accelerator trajectories 112. Large angle collisions, i.e. collisions at scattering angles of 90-180 deg., can change the electromagnetic induction accelerator orbit to a drift orbit. As described above, the direction of rotation of the drift trajectory is determined byCompetition for drift and gradient drift. If it is notDrift dominates, the drift trajectory rotates in the diamagnetic direction. If the gradient drift dominates, the drift trajectory rotates in the diamagnetic direction. This is shown in fig. 13A and 13B. Fig. 13A shows the transition from the electromagnetic induction accelerator orbit to the drift orbit due to a 180 deg. collision, which occurs at point 172. The drift track continues to rotate in the diamagnetic direction becauseThe drift dominates. Fig. 13B shows another 180 ° collision, but in this case the electrostatic field is weak and the gradient drift dominates. The drift track then rotates in the diamagnetic direction.

The direction of rotation of the drift trajectory determines whether it is constrained. Particles moving on the drift trajectory will also have a velocity parallel to the FRC axis. The time taken for a particle to travel from one end of the FRC to the other, as a result of its parallel motion, is called the transit time; thus, the drift trajectory reaches the end of the FRC with a time of the order of the transit time. As indicated with respect to fig. 10A, the lorentz force at the end of the FRC is only constrained to the drift trajectory rotating in the diamagnetic direction. Therefore, ions on the drift trajectory rotating in the diamagnetic direction are lost after the transit time.

This phenomenon leads to an ion depletion mechanism that is expected to exist in all FRC experiments. In fact, in these experiments, the ions carry half the current, while the electrons carry the other half. Under these conditions, the electric field in the plasma is negligible and the gradient drift always exceedsAnd (4) drifting. Thus, all of the drift trajectories caused by large angle collisions are lost after the transit time. These experiments report faster ion diffusivity than those predicted by classical diffusion estimation.

If a strong electrostatic field is present,the drift exceeds the gradient drift and the drift trajectory rotates in the diamagnetic direction. This is shown above with respect to fig. 13A. When these tracks reach the end of the FRC, they are reflected by the lorentz force back into the area of the closed field lines. They are then still constrained in the system.

The electrostatic field in the collision beam system may be strong enough toThe drift exceeds the gradient drift. Thus, by eliminating this ion loss mechanism, similar to the loss cone in a mirror device, the electrostatic field of the system will avoid ion migration.

Another aspect of ion diffusion can be understood by considering the effect of small angle electron-ion collisions on the electromagnetic induction accelerator trajectory. FIG. 14A shows an electromagnetic induction accelerator rail 112; FIG. 14B shows trajectory 174, which is the same trajectory 112 when small angle electron-ion collisions are considered; FIG. 14C shows the track 176 of FIG. 14B followed 10 times longer; and FIG. 14D shows the track 178 of FIG. 14B following 20 times longer. It can be seen that the topology of the electromagnetic induction accelerator orbit does not change due to small angle electron-ion collisions; however, their radial vibration amplitude increases with time. Indeed, in fig. 14A to 14D, over time, this is indicative of classical diffusion.

Formation of FRC

Conventional processes for forming FRCs primarily utilize a theta pinch-field (theta pinch-field) reversal process. In this conventional approach, a bias magnetic field is applied by an external coil surrounding a neutral gas backfill chamber. Once this has occurred, the gas is ionized and the bias magnetic field is frozen in the plasma. Then, the current in the external coil is rapidly reversed and the positively oriented magnetic field lines connect with the previously frozen magnetic field lines to form a closed FRC topology (see fig. 3). This formation process is largely empirical and there is little means to control FRC formation. Therefore, the method has poor repeatability and thus does not have any tuning capability.

In contrast, the FRC formation method of the present invention allows for adequate control and provides a much more transparent and repeatable process. In fact, the FRC formed by the method of the present invention is tunable and its shape and other properties can be directly influenced by manipulation of the magnetic field applied by the external field coil 325. FRC formation by the method of the present invention also results in the formation of electric fields and potential wells in the manner described in detail above. Furthermore, the present method can be easily generalized to accelerate FRC to reactor level parameters and high energy fuel currents, and advantageously enables classical ion confinement. In addition, the present technique can be applied in a compact device and is very reliable and easy to achieve the highly desirable characteristics of all reactor systems.

In the present method, FRC formation is associated with circulating plasma beam 335. It will be appreciated that because the circulating plasma beam 335 is an electric current, it produces a poloidal magnetic field, as does a current in a circular wire. Within the circulating plasma beam 335, the magnetic self-field it induces opposes the externally applied magnetic field caused by the external coil 325. Outside the plasma beam 335, the magnetic self-field is in the same direction as the applied magnetic field. When the plasma current is sufficiently large, the self-field overcomes the applied field and the magnetic field reverses within the circulating plasma beam 335, thus forming an FRC topology as shown on fig. 3 and 5.

The requirement for field reversal can be estimated with a simple model. Consider a beam consisting of a beam having a long radiusAnd short radius＜＜Current carried by the ring. The magnetic field at the center of the ring and orthogonal to the ring is. Supposing that the loop current isBy having an angular velocityIs/are as followsAnd carrying ions. For with radiusThe single ions of the circulating current flow,is an external magnetic fieldThe cyclotron frequency of (c). Suppose thatIs the average velocity of the beam ions. Field reversal is defined as

This means that it is possible to use,＞and is and

whereincm, ion beam energy of. In the one-dimensional model, the magnetic field from the plasma current isWhereinIs the current per unit length. The field reversal requirement is＞=0.225 kilo ampere/cm, wherein=69.3 gauss, and=100 eV. For a model with a periodic ring or rings,averaging over axial coordinates(s is the ring spacing) ifThe model will have the same average magnetic field as the one-dimensional model, where。

Combined beam/electromagnetic induction accelerator formation technique

One preferred method of forming the FRC within the restraint system 300 described above is referred to herein as a combined beam/electromagnetic induction accelerator technique. This method combines low energy plasma ion beams with electromagnetic induction accelerator acceleration using an electromagnetic induction accelerator flux coil 320.

The first step in the method is to inject a substantially annular background plasma cloud into the chamber 310 using the background plasma source 345. The external coil 325 generates a magnetic field within the chamber 310 that magnetizes the background plasma. At short intervals, a low energy ion beam is implanted into the chamber 310 through an injection port 340 that substantially traverses the applied magnetic field within the chamber 310. As explained above, the ion beams are trapped within the chamber 310 on a large electromagnetic induction accelerator orbit by this magnetic field. These ion beams may be generated by ion accelerators, such as accelerators including ion diodes and Marx generators. (see R.B. Miller, An Introduction to the Physics of Intense Charged Particle beams (enhanced Charged Particle beam Physics Introduction), (1982)). As will be appreciated by those skilled in the art, upon entry of the implanted ion beam into the chamber 310, the applied magnetic field will exert a lorentz force thereon. However, it is desirable that the ion beam not deflect and thus not enter the electromagnetic induction accelerator orbit before reaching the circulating plasma beam 335 beam. To address this problem, the ion beam is neutralized with electrons and then, as illustrated in fig. 15, positively charged ions and negatively charged electrons are separated as the ion beam 350 is directed through an appropriate magnetic field, such as a unidirectionally applied magnetic field within the chamber 310. The ion beam 350 thus acquires electric self-polarization due to the magnetic field. This magnetic field may also be generated by, for example, permanent magnets or electromagnets along the ion beam path. Upon subsequent introduction into the confinement chamber 310, the resulting electric field balances the magnetic forces experienced by the beam particles, allowing the ion beam to drift without being deflected. Fig. 16 shows a front view of the ion beam 350 as it contacts the plasma 335. As depicted, electrons from the plasma 335 travel along magnetic lines into or out of the beam 350, which thereby consumes the electrical polarization of the beam. When the beam is no longer electrically polarized, the beam joins a circulating plasma beam 335 on the electromagnetic induction accelerator orbit about the principal axis 315, as shown in fig. 1 (see also fig. 5).

As the plasma beam 335 travels on its electromagnetic induction accelerator track, these moving ions form a current that in turn causes a poloidal magnetic self-field. To create an FRC topology within chamber 310, it is necessary to increase the speed of plasma beam 335, thereby increasing the magnitude of the magnetic self-field induced by plasma beam 335. When the magnetic self-field is sufficiently large, the direction of the magnetic field within the plasma beam 335 at a radial distance from the axis 315 reverses, resulting in FRC. (see FIGS. 3 and 5). It will be appreciated that to maintain the radial distance of the circulating plasma beam 335 on the accelerator orbit, it is necessary to increase the applied field of the outer coil 325 as the circulating plasma beam 335 increases in velocity. Thus, a control system is provided for maintaining a suitable externally applied magnetic field governed by the current through the external coil 325. Alternatively, a second external coil may be used to provide the additional externally applied magnetic field, which is required to maintain the radius of the trajectory of the plasma beam as it is accelerated.

To increase the velocity of the circulating plasma beam 335 on its trajectory, an electromagnetic induction accelerator flux coil 320 is provided. Referring to fig. 17, it can be appreciated that increasing the current through the electromagnetic induction accelerator flux coil 320 induces an azimuthal electric field E within the chamber 310, in ampere's law. Positively charged ions in the plasma beam 335 are accelerated by this induced electric field, resulting in field reversal as described above. When ion beam 350 (which is neutralized and polarized as described above) is added to circulating plasma beam 335, plasma beam 335 depolarizes the ion beam.

For field reversal, the circulating plasma beam 335 is preferably accelerated to a rotational energy of about 100 eV, and preferably about 75 eV to 125 eV. To achieve the relevant conditions for fusion, the circulating plasma beam 335 is preferably accelerated to about 200 KeV, and preferably to about 100 KeV to 3.3 MeV.

The formation of FRCs using a combined beam/electromagnetic induction accelerator formation technique was successfully demonstrated. With an applied magnetic field of up to 500G, a magnetic field induced from the rotating plasma by the electromagnetic induction accelerator flux coil 320 of up to 5kG, and 1.2The torr vacuum, combined beam/electromagnetic induction accelerator formation technique was performed on a chamber 1 liner of 1 meter diameter and 1.5 meters length. In the experiment, the background plasma hadThe ion beam is ofThe density of,A neutral hydrogen beam with a pulse length of about 20 mus (at half height). A field reversal is observed.

Electromagnetic induction accelerator forming technology

Another preferred method of forming the FRC within the restraint system 300 is referred to herein as an electromagnetic induction accelerator formation technique. This technique is based on directly driving the electromagnetic induction accelerator induction current with the electromagnetic induction accelerator flux coil 320 to accelerate the circulating plasma beam 335. One preferred embodiment of this technique utilizes the confinement system 300 depicted in fig. 1, except that implantation of a low energy ion beam is not necessary.

As indicated, the primary component in the electromagnetic induction accelerator formation technique is an electromagnetic induction accelerator flux coil 320 mounted centrally in the chamber 310 and along its axis. Due to its separate and wound structure, the coil 320 exhibits very low inductance and has a low LC time constant when coupled to a suitable power supply, which enables a rapid jump in current in the flux coil 320.

Preferably, the formation of FRC is initiated by energizing the external magnetic field coils 325, 330. This provides an axially directed magnetic field near the end and a radial magnetic field component to axially confine the plasma injected into the chamber 310. Once a sufficient magnetic field is established, the background plasma sources 345 are energized by their own power supply. The plasma emitted from the torch directs the magnetic field flow in an axial direction and disperses slightly due to its temperature. When the plasma reaches the mid-plane of the chamber 310, a continuous, axially extending, annular layer of cold slow moving plasma is established.

At this time, the electromagnetic induction accelerator induction flux coil 320 is excited. The rapidly rising current in the coil 320 causes a rapidly changing axial magnetic flux inside the coil. This rapid increase in axial flux, by virtue of the inductive effect, causes the generation of an azimuthal electric field E (see fig. 18) that passes through the space surrounding the flux coil. This electric field E is proportional to the change in the intensity of the magnetic flux in the coil, according to maxwell's equations, i.e., faster jumps in the current of the electromagnetic induction accelerator coil will result in a stronger electric field.

The inductively generated electric field E couples with the charged particles in the plasma to cause a ponderomotive force that accelerates the particles in the toroidal plasma layer. By virtue of their smaller mass, electrons are the first species subject to acceleration. The initial current formed by this process is then mainly caused by electrons. However, a sufficient acceleration time (on the order of hundreds of microseconds) will also eventually result in an ion current. Returning to fig. 18, this electric field E accelerates electrons and ions in opposite directions. Once the two species reach their final velocities, the current is almost equally carried by the ions and electrons.

As described above, the current carried by the rotating plasma results in an auto-magnetic field. The creation of the actual FRC topology is created when the self-magnetic field created by the current in the plasma layer becomes comparable to the applied magnetic field from the external field coils 325, 330. At this time, magnetic reconnection occurs, and the open magnetic lines of the initial externally generated magnetic field begin to close and form an FRC flux surface (see fig. 3 and 5).

The fundamental FRC established by this method exhibits modest magnetic fields and particle energies, which are generally not at reactor-related operating parameters. However, as long as the current in the electromagnetic induction accelerator flux coil 320 continues to increase at a rapid rate, the induced electric acceleration field will continue to exist. The effect of this process is that the energy and total magnetic field strength of the FRC continues to increase. The extent of this process is then limited primarily by the flux coil power supply, since large-scale energy storage is required to continue to deliver current. However, in principle, the conditions associated with accelerating the system to the reactor are straightforward.

For field reversal, the circulating plasma beam 335 is preferably accelerated to a rotational energy of about 100 KeV, preferably in the range of about 75 KeV to 125 KeV. To achieve fusion-related conditions, the circulating plasma beam 335 is preferably accelerated to about 200 KeV, preferably in the range of about 100 KeV to 3.3 MeV. When the ion beam is added to the circulating plasma beam 335, the plasma beam 335 depolarizes the ion beam, as described above.

FRC formation using the electromagnetic induction accelerator formation technique was successfully demonstrated at the following parameter levels:

vacuum chamber size: about 1 meter diameter, 1.5 meters long;

10cm of electromagnetic induction accelerator coil radius;

a plasma orbit radius of 20 cm;

the average external magnetic field generated inside the vacuum chamber reaches 100 gauss, a 150 microsecond ramp cycle and a2 to 1 ratio of the magnetic mirror (source: external coil and electromagnetic induction accelerator coil);

background plasma (essentially hydrogen) characterized by about 10¹³cm^-3An average density of less than 10 eV, a kinetic temperature of less than 10 eV;

the lifetime of this configuration is limited by the total energy stored in the experiment, typically around 30 microseconds.

Experiments were conducted by first injecting a background plasma layer with two sets of coaxial cable guns mounted in a circular shape inside the chamber. One set of 8 guns each is mounted on one of two mirror coil sets. The guns are equally spaced apart in azimuth and offset from the other sets. This arrangement allows the guns to fire simultaneously and thereby create an annular plasma sheath.

When this layer is established, the electromagnetic induction accelerator flux coil is energized. The rising current in the winding of the electromagnetic induction accelerator coil causes an increase in magnetic flux within the coil, which causes the azimuthal electric field to curl around the induction accelerator coil. The fast ramp and high current in the flux coil of the electromagnetic induction accelerator creates a strong electric field that accelerates the torroidal plasma layer, thereby inducing a significant current. A sufficiently strong plasma current generates a magnetic self-field that alters the applied field and causes the formation of a field-reversed configuration. The range, intensity and duration of the FRC are identified using detailed measurements of the B-dot loop.

In fig. 19, an example of typical data is shown by a trace of a B-shaped point detection signal. Data curve a represents the absolute strength of the axial component of the magnetic field at the axial midplane of the laboratory (75 cm from any end plate) and at a radial position of 15 cm. Data curve B represents the absolute strength of the axial component of the magnetic field at the axial midplane of the chamber and at a radial position of 30 cm. Thus, the curve a data set represents the magnetic field strength within the fuel plasma layer (between the magnetic induction accelerator coil and the plasma), while the curve B data set depicts the magnetic field strength outside the fuel plasma layer. These data clearly show that the internal magnetic field reverses orientation (is negative) between about 23 microseconds to 47 microseconds, while the external field is still positive, i.e. not in reverse orientation. The time of reversal is limited by the jump in current in the coil of the electromagnetic induction accelerator. Once the peak current is reached in the electromagnetic induction accelerator coil, the current in the fuel plasma layer begins to decrease and the FRC decays rapidly. FRC life has been limited by the energy that can be stored in experiments to date. As with the injection and capture experiments, the system can be upgraded to provide longer FRC life and speed up to reactor related parameters.

In summary, the present technique not only produces a compact FRC, but is also affordable and simple to implement. Most importantly, the base FRC produced with the present method can be easily accelerated to any desired level of rotational energy and magnetic field strength. This is crucial for fusion applications and classical confinement of high energy fuel beams.

Inductive plasma source

The described electromagnetic induction accelerator and beam/electromagnetic induction accelerator FRC formation techniques, both rely on the background plasma being energized by the flux coil 320. Similar to the transformer, the flux coil performs the function of the primary winding of the transformer, while the plasma functions as the secondary winding. For this induction system to work efficiently, it is absolutely necessary that the plasma be a good conductor.

In contrast to a typical conductor such as a metal, the resistance of the plasma becomes smaller and thus more conductive as its temperature increases. In particular, the temperature of the plasma electrons plays an important role, largely determining the dissipation (associated with electron-ion collisions). Essentially, the dissipation is due to the resistance caused by electron-ion collisions: the higher the impact frequency, the higher the resistivity. This is due to polymerization phenomena in the plasma, in which the coulomb collision cross-section is shielded. The collision frequency (incidence of successive collisions) is essentially the density, the shielded coulomb scattering cross-section and the thermal (or average) velocity (i.e. the collision/scattered charge)) As a function of (c). By definition, v and T^1/2Proportional, σ and v-⁴In proportion to, or, thus, T^-2And (4) in proportion. Therefore, the frequency of collisionAnd n T^-3/2And (4) in proportion. Resistivity is as followsA relationship is established with the collision frequency. Thus, resistivity and T^-3/2Proportionally, and notably, independent of density, a direct consequence of this fact is that even if the number of charge carriers increases with density, the number of scattering centers increases. Thus, higher temperatures result in higher plasma conductivity and less dissipative losses.

Thermal plasma is highly desirable for this purpose to achieve better performance of confinement in FRC. In the case of PEG systems, increased electron temperature leads to improved FRC starting (plasma becomes the better conductor, better inductive coupling between plasma and flux coil), better current sustaining (reduced plasma resistivity leads to less friction/dissipation losses and thus less current losses), and higher magnetic field strength (stronger current, larger self-field). Sufficient electron temperature during initial plasma formation and prior to flux coil engagement will result in better coupling of the flux coil to the plasma (which advantageously tends to reduce the formation of azimuthal image currents in the chamber walls). This in turn will result in enhanced electromagnetic induction accelerator acceleration (less resistivity leading to better inductive transfer of energy from the flux coil to the plasma) and plasma heating (some of the imparted directed energy represented by the rotating current thermalizes and turns to random energy-ultimately leading to plasma heating by the flux coil), which will thus increase ion-electron collision time (due to higher temperature), reduce dissipation (less resistivity), and ultimately create conditions for reaching higher FRC magnetic fields (higher current leading to stronger magnetic fields).

To achieve a better initial plasma temperature, an inductive plasma source is provided. As depicted in fig. 20A, 20B and 20C, an inductive plasma source 1010 is mountable within the chamber 310 around the end of the flux coil 320 and includes a single turn bribered assembly 1030, the assembly 1030 preferably being fed with a high voltage (about 5-15 KV) power supply (not shown). Neutral gases such as hydrogen (or other suitable gaseous fusion fuel) are introduced into the source 1010 by direct gas feed through a Laval (Laval) nozzle 1020. The air flow is preferably controlled by groups of ultrafast spray valves to produce a cleaning impact front. Once the gas exits the nozzle 1020 and distributes itself over the surface of the coil windings 1040 of the briberbed 1030, the windings 1040 are energized. The ultrafast current and flux jump in the low inductance coils 1030 results in a very high electric field within the gas that causes breakdown, ionization and subsequent injection of the formed plasma from the surface of the coils 1030 to the center of the chamber 310.

In a preferred embodiment, the briberring 1030 includes an annular disk shaped body 1032 bounded by an outer ring 1034 formed around its outer periphery and an annular hub 1036 formed around its inner periphery. The ring 1034 and hub 1036 extend axially beyond the surface of body 1032 to form an open annular channel 1035. Body 1032, ring 1034 and hub 1036 are preferably formed by integral molding of a suitable non-conductive material having good vacuum properties and low outgassing properties, such as glass, plexiglass, pirex, quartz, or ceramic, among others.

A multi-segmented shroud (shroud) 1012 is preferably coupled to ring 1034 of briberring 1030 to limit the radial drift of the generated plasma. Each segment 1014 of the sleeve 1012 includes a plurality of axially extending fingers 1016. The end of each segment 1014 includes a mounting bracket 1015.

The coil windings 1040 are preferably attached to the face of the coil body 1032 within the channel 1035 with epoxy or some other suitable adhesive. To obtain the fast electromagnetic characteristics of briberband 1030, it is important to keep its inductance as low as possible. This is achieved by using as few turns as possible in the coil 1040 and making the coil 1040 from a multi-strand, parallel-wound wire 1042. In one exemplary embodiment, the coil 1040 includes 24 parallel strands 1042, each completing one turn. These wires 1042 each start at entry points that are preferably located about 15 degrees apart on the outer circumference of body 1032 and end at exit points 1046 on the inner diameter of body 1032 after only one turn around the shaft. Thus, the coil windings 1040 cover the entire area between the inner and outer edges of the channel 1035. Preferably, the set of strands 1042 are connected to the same capacitive storage volume. In general, power can be fed to all of the strands 1042 from the same capacitive storage volume, or, as in one exemplary embodiment, 8 sets of 3 strands 1042 are all connected together, fed in common by one of 2 separate capacitive storage volumes.

The annular disk shaped nozzle body 1022 is joined around its inner periphery to the hub 1036 to form the Laval nozzle 1020. A surface 1024 of the nozzle body 1022 facing the hub 1036 has an expanded, mid-pitch contour defining an annular gas manifold 1025 between the surface 1024 and a face 1037 of the hub 1036. Adjacent to the outer perimeter of the nozzle body 1022, the surface 1024 has a converging to diverging profile defining an azimuthally extending laval-type nozzle outlet 1023 between the surface 1024 and the face 1037 of the hub 1036.

Attached to the opposite face of the hub 1036 is a valve seat ring 1050, with several valve seats 1054 formed in the outer face of the ring 1050. The valve seat 1054 is aligned with the gas feed channel 1052 formed by the hub 1036.

In operation, neutral gas is fed through the ultrafast nozzle valve in the valve seat 1054 to the gas passage 1052 extending through the hub 1036. Because of the constricted portion of the nozzle outlet 1023, the gas tends to feed into and fill the annular gas manifold 1025 before exiting the nozzle 1020. Once the gas exits the nozzle 1020 and distributes itself over the surface of the coil windings 1040 of the briberbed 1030, the windings 1040 are energized. The ultrafast current and flux jump in low inductance coils 1030 results in a very high electric field within the gas that causes breakdown, ionization and subsequent injection of the formed plasma from the surface of the coils 1030 to the center of the chamber 310.

The current jumps are preferably well synchronized in all strands 1042 or groups of strands 1042 that are intended to be fired together. Another option, which is possible and advantageous, is to ignite the different sets of strands at different times. A delay may be intentionally established between the participating different sets of strands 1042 to enable the different sets of strands to be started at different times. When different sets of strands are activated at different times, it is important to group the strands in a manner such that the arrangement is azimuthally symmetric and provides adequate coverage of the current carrying wires 1042 for the surface of the coil 1040 at any given power pulse. The delay between pulses is limited by how much neutral gas is available. In practice, it is possible to fire such pulses 5-600 microseconds apart.

In practice, the input operating parameters are preferably as follows:

charging voltage: split phase power supply of about 10 to 25 kV

Current: total current up to about 50 kA is passed through all windings combined

Pulse/rise time: up to about 2 microseconds

Gas pressure: about-20 to 50psi

The size of the gas header is as follows: about 0.5 to 1cm per valve³I.e. about 4 to 8cm per shot (per shot)³Total gas volume

In an exemplary embodiment, the input operating parameters are as follows:

charging voltage: 12 to 17kV split-phase power supply, i.e. -12 KV to +12 KV

Current: a total current of 2 to 4.5kA per 3-strand group, i.e. 16 to 36kA, is passed through all windings combined

Pulse/rise time: 1 to 1.5 microseconds

Gas pressure: about-15 to 30psi

Inflation size: 0.5 to 1cm per valve³I.e. 4 to 8cm per shot³Total gas volume

The plasma produced by this method of operation of inductive plasma source 1010 using the parameters described above has the following advantageous characteristics:

density 4X10¹³cm^-3

The temperature is 10-20 eV

Ring scale-40-50 cm diameter

Axial drift velocity of 5-10 eV

Due to the shape and orientation of the source 1010, the shape of the flood plasma is annular and has a diameter equal to the rotating plasma torus of the FRC to be formed. In the present PEG system, two such inductive plasma sources 1010 are preferably placed at either axial end of the chamber 310, and are preferably fired in parallel (fire). The two formed plasma distributions drift axially toward the center of the chamber 310 where they form an annular plasma layer, and the plasma is then accelerated by the flux coil 320, as described above.

RF drive of ions and electrons in FRC

RF (radio frequency) current drives (called rotomak) have been addressed for FRC applications, where the current is carried primarily by electrons. It involves generating a rotating radial magnetic field by two phased antennas. The electrons are magnetized and frozen onto the rotating magnet line. This holds the current until the ions are accelerated and the current is reduced by coulomb collisions with electrons. Rotomak, while not suitable for holding current indefinitely, has been successful for a few milliseconds.

In the FRC of the present system, the current is carried primarily by ions on the electromagnetic induction accelerator orbit, which are not frozen onto the rotating magnet line. Large orbitals are important for stability and classical diffusion. Instead of an antenna, electrons and ions are driven by electrostatic waves as in a cyclotron. The problem is completely electrostatic because the RF frequency is less than 10 megacycles, so that the wavelength (30 meters) is much longer than any plasma size. Electrostatic fields can pass through FRC plasmas much more easily than electromagnetic waves.

The electrostatic wave generated by the electrodes is designed to propagate at a near-mean azimuthal velocity of the ions. If this wave propagates faster than the average velocity of the ions, it will accelerate them and thus compensate for the drag due to ion-electron collisions. However, the electrons are also accelerated by collisions with the departing coulombs. In this case the wave must have a slower speed than the average speed of the electrons, which will accelerate the wave. The average electron velocity is less than the average ion velocity, so the electrons must be driven at two different frequencies. The higher frequency will be for ions and is preferably energized by an external circuit. For electrons, energy can be obtained at a lower frequency.

Electrode system

A quadrupole RF drive system is shown in fig. 21A and 21B. As depicted, the RF drives a quadrupole cyclotron 1110 that includes an elongated, azimuthally symmetric electrode 1112 located within the chamber 310 and having 4 gaps 1114 therebetween. The quadrupole cyclotron 1110 preferably generates a potential wave that rotates in the same direction as the azimuthal velocity of the ions, but at a greater velocity. Ions of appropriate velocity can be trapped in this wave and periodically reflected. This process increases the momentum and energy of the fuel ions, and this increase is transferred to the fuel ions that are not trapped by collisions. Fuel ions from the plasma 335 may be replaced by injecting neutral particles at any conventional rate.

An alternative method of supplementing the excitation current is to augment the electrode system with additional magnetic field coils 1116 placed near the flux coil 325 and the quadrupole cyclotron 1110 and to excite these coils at half the frequency of the cyclotron electrode 1112. However, the following discussion provided herein is intended to illustrate the only version of the electrode (without the field coil 1116).

Electrodes of the 2 and 4 electrode configurations are illustrated in fig. 21C.

Shown on FIG. 21C for space r < r_bVacuum, potential generated by the electrodes with the applied voltage shown. Those expressions are for the lowest harmonics. They are obtained by solving the laplace equation below with appropriate boundary conditions.

In the case of a two-pole cyclotron,

to a （6）

=To a

Is limited.

Due to the fact thatPeriodic by 2 π in θ, so that it can be expanded into a Fourier series, i.e.

And, u_nSatisfy the equation

If n =2, 4 …, etc., then

=0

The lowest harmonic is

The higher harmonic is

The wave velocity in the azimuth direction isThe higher harmonics have smaller phase velocities and amplitudes. These comments apply to both cases on fig. 21C. When the FRC rigid rotor is balanced, the frequency omega approaches the ion rotation frequency omega_i. Thus, for=1，. For the=2，And the wave amplitude will be much lower; therefore, considering only the lowest harmonics is a good approximation.

Plasma effect

The response of the plasma can be described by the dielectric tensor. The electric field generates a plasma current according to the following conservation of charge equation, which generates charge separation.

Wherein the content of the first and second substances,is the current density and ρ is the charge density. The appropriate equation is

Or

Wherein the content of the first and second substances,is the dielectric tensor that is present,is the polarizability. Tensor, if it comprises contributions of electrons onlyIs diagonal, one component is.

Where n is the density and B is the FRC magnetic field. n and B vary rapidly with r, with r = r within the plasma₀B =0 on the face of (a). Assuming that the electrons have a small radius of gyration and are at the same frequency of gyrationThe comparative electric field changes slowly and is derivedIs described in (1). This approximation does not hold around the zero plane. The characteristic orbit changes from a drift orbit to an electromagnetic induction accelerator orbit with much less response to the electric field, i.e. at r = r₀Near the zero plane of. The ions have predominantly an electromagnetic induction accelerator orbit, and for a drift orbit, the response to the electric field is small because the electric field is at a rateAnd (4) changing.

The net result is that the Laplac equation is replaced by the following equation

It must be solved numerically. At r = r₀Nearby additional items disappear. For the quadrupole case, the potential of the lowest harmonic has the following form

With a similar form for the dipolar case. Waves propagating in the opposite direction to the ions (or electrons) will be ignored.

Acceleration caused by ions trapped in an electrostatic wave

We assume that,so as to waveA little faster than the ions. Assuming a standard rigid rotor distribution function for ions

The distribution function of interest to reduce is

The wave velocity of the electrostatic wave generated by the quadrupole cyclotron is. If it is not

The ions move faster than the wave reflects.

This increases the amount of wave energy, i.e.,

if it is not

The ion motion is slower than the wave reflection and the wave loses energy at the following rate

Net outcome variableThe change of (a) is simplified, that is,

approximation

Result in

This has a similar form to that of landau damping, but is not physically the same, since landau damping (growth) is a linear phenomenon, which is clearly non-linear.

Due to the fact that

If it is notThere is no change in the wave energy. If it is notOrWave energy is reduced; for theThe wave energy increases. This is similar to the explanation for landau damping. In the first caseIn the following, ions slower than the wave travel are more than ions faster than the wave travel. Thus, the wave energy is reduced. In the opposite caseThe wave energy increases. The former case is suitable for maintaining ion energy and momentum with a quadrupole cyclotron. This is current drive. The latter case provides the basis for the converter. Equations (22) and (23) can be used to evaluate the suitability for fusion reactor conditions.

In that(ion thermal velocity) the power delivered to the ions is

Wherein the content of the first and second substances,determined by equations (24) and (25).

For simplifying integration, use(value at peak density, lower limit of wave amplitude)。

Is the linear density of the ions. i =1,2 accommodates two types of ions, which is typically the case in a reactor.

The detailed calculation of (2) shows that the wave amplitudeIs the maximum gap voltage (2V)₀) About one-10 times lower. This will determine the limitations of this RF driving method. V₀Will be limited by the maximum gap voltage that can be maintained (perhaps about 10 kV for a 1cm gap).

Reactor requirements

For current driving, preferably at frequencyPower P of handlebar_iIs transferred to the ions and, preferably, at a frequencyPower P of handlebar_eTo the electrons. This will compensate for the coulomb interaction between the electrons and ions, which reduces the ion velocity and increases the electron velocity. (without power transfer, Coulomb collisions would lead to electron and ionAt the same speed and no current). The average electric field for maintaining electron and ion balance is given by

Wherein the content of the first and second substances,is the current per unit length of the current,

is resistance per unit length.、、Is the linear density of electrons and ions,wherein、Is the atomic number of the ion;andthe momentum transfer time from the ion to the electron. The average electric field is the same for ions or electrons becauseIn the light of the quasi-neutrality,and the charges are opposite. The power that must be delivered to the ions is

The power that can be obtained from the electrons is

Wherein the content of the first and second substances,and。

to refuel with RF drive, the fuel can be fired at fusion timeAndgiven rate of change at any energy, n₁And n₂Is the ion density of the plasma and is,is the reaction rate. The number is in seconds. Injected neutral species (instead of fuel ions that disappear from combustion) will be in milliseconds (for 10) due to coulomb collisions¹⁵cm^-3Reactor density of the order of magnitude) rapidly ionizes and accelerates to an average ion velocity. However, this needs to be rightAnd an increase in power transfer to maintain a steady state. The increase is

It will increase the power transfer required by a factor of about 2.

Power can be supplied to the current drive and refuelling without exceeding a maximum gap voltage amplitude of 10 kV/cm. Considering that the frequency would be 1-10 mhz and the magnetic field would be 100 kilogauss, no breakdown would be expected. The power that must be delivered for current drive and refuelling is the same for any current drive method. However, RF technology at 1-10 MHz has been an efficient technology established for many years. The method using electrodes instead of antennas has considerable advantages because the conditions for field penetration are much more relaxed than for electromagnetic waves. Therefore, this method has the advantages of cyclic power and efficiency.

Fusion of

Significantly, these two techniques or other similar techniques for forming an FRC within the closed system 300 described above are capable of producing a plasma having properties suitable for causing nuclear fusion therein. More particularly, the FRC formed by these methods can be accelerated to any desired level of rotational energy and magnetic field strength. This is crucial for fusion applications and classical confinement of high energy fuel beams. Thus, in the confinement system 300, it is possible to trap and confine the high-energy plasma beam for a period of time sufficient to cause fusion reactions thereof.

To accommodate fusion, the FRC formed by these methods is preferably accelerated to the appropriate level of rotational energy and magnetic field strength by electromagnetic induction accelerator acceleration. However, for any reaction to occur, fusion may require a specific set of physical conditions. Furthermore, to achieve efficient fuel burn-up and achieve a positive energy balance, the fuel must remain substantially unchanged for long periods of time. This is important because high dynamic temperatures and/or energies characterize fusion-related states. Therefore, the establishment of this state requires a considerable energy input, which can be recovered only if most of the fuel undergoes fusion. As a result, the fuel constraint time must be longer than its combustion time. This results in a positive energy balance, resulting in a net energy output.

It is a significant advantage of the present invention that the confinement system and plasma described herein are capable of long confinement times, i.e., confinement times that exceed the time of combustion of the fuel. The typical state of fusion is then characterized by the following physical conditions (which vary depending on the fuel and the mode of operation):

average ion temperature: about 30 to 230 keV, preferably about 80keV to 230 keV;

average electron temperature: about 30 to 100 keV, preferably about 80 to 100 keV;

coherent energy of fuel beam (ion beam implantation and circulating plasma beam): about 100 keV to 3.3MeV, preferably about 300keV to 3.3 MeV;

total magnetic field: about 47.5 to 120kG, preferably about 95 to 120kG (applied magnetic field of about 2.5 to 15kG, preferably about 5 to 15 kG);

classical constraint time: greater than the fuel burn time, preferably about 10 to 100 seconds;

fuel ion density: about 10¹⁴To less than 10¹⁶cm^-3Preferably about 10¹⁴To 10¹⁵cm^-3；

Total fuel power: in the range of about 50 to 450 kW/cm (power per cm of chamber length)

To accommodate the fusion conditions specified above, the FRC is preferably accelerated to a level of coherent rotational energy, preferably about 100 keV to 3.3MeV, more preferably about 300keV to 3.3MeV, and the magnetic field strength level is preferably about 45 to 120kG, more preferably 90 to 115 kG. At these levels, a high energy ion beam (neutralized and polarized as described above) can be implanted into the FRC and trapped to form a plasma beam layer in which the plasma beam ions are magnetically confined and the plasma beam electrons are electrostatically confined.

Preferably, the electron temperature is kept as low as practical to reduce the amount of bremsstrahlung that could otherwise result in radiative losses. The electrostatic energy trap of the present invention provides an effective means to achieve this.

The ion temperature is preferably maintained at a level that provides efficient burn-up, as the fusion cross-section is a function of ion temperature. The high direct energy of the fuel ion beam is necessary to provide classical mobility, as discussed in this application. It also minimizes the effect of instability on the fuel plasma. The magnetic field is consistent with the beam rotation energy. It is partially generated by the plasma beam (self-field), which itself provides support and force to maintain the plasma beam on the desired trajectory.

Fusion products

Fusion products are generated in the power core primarily near the null plane 86, and they emerge therefrom by diffusing toward the interface plane 84 (see fig. 3 and 5). This is due to collisions with electrons (because collisions with ions do not change the centroid, they are not caused to change the field lines). Because of their high kinetic energy (fusion product ions have much higher energy than fuel ions), fusion products can easily cross the interface 84. Once they pass beyond the interface 84, they can exit along the open field lines 80 as long as they experience scattering from ion-ion collisions. Although this collision process does not result in diffusion, it can change the direction of the ion velocity vector so that it is directed parallel to the magnetic field. These open field lines 80 connect the FRC topology of the core with a uniform externally applied magnetic field provided outside the FRC topology. The product ions emerge at different field lines along which they follow with an energy distribution. Advantageously, product ions and charge-neutralizing electrons emerge from both ends of the fuel plasma in the form of rotating annular bundles. For example, for 50 megawattsp-B¹¹By design of the reaction, these beams will have a radius of about 50cm and a thickness of about 10 cm. In the strong magnetic field (typically around 100 kGauss) found outside the interface 84, the product ions have a relevant radius of gyration distribution that varies from a minimum of about 1cm to a maximum of around 3cm for the highest energy product ions.

Initially, the product ion has a structure ofAndlongitudinal as well as rotational energy. v. of_perpIs the azimuthal velocity associated with rotation about the field line as the center of the orbit. As the field lines diverge away from the vicinity of the FRC topology, the rotational energy is reduced while the total amount remains unchanged. This is a result of adiabatic invariance of the magnetic moment of the product ions. It is well known in the art that charged particles that orbit in a magnetic field have a magnetic moment that is related to their motion. In the case of particles moving along a slowly varying magnetic field, there are also particles ofAdiabatic invariance of the described motion. The product ions that follow around their respective magnetic flux orbit have a magnetic moment and such adiabatic invariance in relation to their motion. Since B decreases to 1/10 (indicated by the dispersion of the field lines), it follows that v_perpAlso reduced to about 1/3.2. Thus, by the time the product ions reach the homogeneous field, their rotational energy will be less than 5% of their total energy. In other words, almost all of the energy is in the longitudinal component.

Energy conversion

The direct energy conversion system of the present invention comprises an Inverse Cyclotron Converter (ICC) 420, as shown on fig. 22A and 23A, which is coupled to a power core 436 of a Collision Beam Fusion Reactor (CBFR) 410, constituting a plasma power generation system 400. A second ICC (not shown) can be placed symmetrically to the left of CBFR 410. The magnetic cusp 486 is located between the CBFR 410 and ICC 420 and is formed when the CBFR 410 and ICC 420 magnetic fields meet.

Before describing ICC 420 and its operation in detail, a review of a typical cyclotron is provided. In a conventional cyclotron, high-energy ions having a velocity perpendicular to a magnetic field rotate in a ring. The orbital radius of high-energy ions is determined by the magnetic field strength and their charge-to-mass ratio and increases with energy. However, the rotational frequency of the ions is independent of their energy. This fact has been exploited in the design of cyclotron accelerators.

Referring to fig. 24A, a conventional cyclotron 700 includes two mirrored C-shaped electrodes 710 that make up a D-shaped cavity placed in a uniform magnetic field 720, the uniform magnetic field 720 having field lines that are perpendicular to the plane of symmetry, i.e., the page, of the electrodes. An oscillating potential is applied between the C-shaped electrodes (see fig. 21B). Ions I emanate from a source placed in the center of the cyclotron 700. The magnetic field 720 is adjusted so that the frequency of rotation of the ions matches the frequency of the electric potential and the associated electric field. An ion I is accelerated if it crosses the gap 730 between the C-shaped electrodes 710 in the same direction as the direction of the electric field. By accelerating the ion I, its energy and orbital radius increase. When the ion has traveled a half-arc (without experiencing an increase in energy), it again passes over the gap 730. The electric field between the C-shaped electrodes 710 has now reversed direction. The ion I is accelerated again and its energy is further increased. This process is repeated each time an ion crosses the gap 730, provided that the rotational frequency of the ion continues to match the frequency of the oscillating electric field (see fig. 24C). Conversely, if a particle crosses the gap 730 when the electric field is in the opposite direction, it will be decelerated back to the central source. Only particles having an initial velocity perpendicular to the magnetic field 720 that cross the gap 730 at the appropriate phase of the oscillating electric field will be accelerated. Therefore, proper phase is important for acceleration.

In principle, a cyclotron can be used to extract kinetic energy from a pencil beam of the same high-energy ions. Deceleration with a cyclotron has been observed for protons without energy extraction, as described by Bloch and Jeffries in "physical reviews", 80, 305 (1950). Ions can be implanted into the cavity so that they enter a deceleration phase relative to the oscillating field. All these ions will then reverse the trajectory T of the accelerated ions as shown on figure 24A. As the ions slow down due to interaction with the electric field, their kinetic energy is converted into oscillating electric field energy in the circuit of which the cyclotron is a part. A direct conversion to electrical energy will be achieved which will occur with a very high efficiency.

In practice, the ions of the ion beam will enter the cyclotron in all possible phases. Unless the varying phase is compensated for in the cyclotron design, half of the ions will be accelerated and the other half will be decelerated. As a result, the maximum conversion efficiency will actually be 50%. Furthermore, the annular fusion product ion beam discussed above is an inappropriate geometry for a conventional cyclotron.

As discussed in greater detail below, the ICC of the present invention accommodates the toroidal character of the fusion product beam of the FRC exiting the fusion reactor power core, and the random phase of the ions within the beam and their dispersion in energy.

Returning to fig. 22A, a portion of the power core 436 of the CBFR 410 is illustrated on the left, with the plasma fuel core 435 confined in the FRC 470 formed in part due to the magnetic field applied by the external field coil 425. The FRC 470 includes closed field lines 482, an interface 484, and open field lines 480. As noted above, FRC 470 determines the properties of the annular beam 437 of fusion products. The open field force wire 480 extends away from the power core 436 toward a cusp (cusp) 486. As noted above, fusion products emerge from the power core 436 along the open field lines 480 in the form of an annular beam 437 containing high energy ions and charge-neutralized electrons.

The ICC 420 has a geometry like a hollow cylinder with a length of about 5 meters. Preferably, 4 or more semi-cylindrical electrodes 494 with small straight slits 497 form a cylindrical surface. In operation, an oscillating electrical potential is applied to electrode 494 in an alternating manner. The electric field E within the converter has a quadrupole structure as illustrated on the end view shown on fig. 22B. The electric field E disappears on the symmetry axis and linearly increases along with the radius; the peak is at the gap 497.

Furthermore, the ICC 420 comprises an external field coil 488 that forms a uniform magnetic field within the hollow cylinder geometry of the ICC. Because current flows through ICC field coil 488 in the opposite direction to the direction of current flowing through CBFR field coil 425, field lines 496 in ICC 420 run in the opposite direction to the direction of open field lines 480 of CBFR 410. At the furthest end of the power core 436 from the CBFR 410, the ICC 420 includes an ion collector 492.

Between CBFR 410 and ICC 420 is a symmetric magnetic cusp 486 where open field lines 480 merge with field lines 496 in ICC 420. An annular electron collector 490 is positioned around the magnetic cusp 486 and is electrically coupled to the ion collector 492. The magnetic field of the magnetic cusp 486 converts the axial velocity of the beam 437 to rotational velocity with high efficiency, as described below. Fig. 22C illustrates a typical ion trajectory 422 within the converter 420.

CBFR 410 has cylindrical symmetry. At its center is fusion power core 436, fusion plasma core 435 is contained in the FRC 470 magnetic field topology where fusion reactions occur. As noted, product nuclei and charge-neutralized electrons emerge from both ends of the fuel plasma 435 as an annular beam 437. For example, for a 50 megawatt p-B¹¹By design of the reaction, these beams will have a radius of about 50cm and a thickness of about 10 cm. The annular beam has density n ≈ 10⁷-10⁸cm³. For such densities, the magnetic cusps 486 separate electrons and ions. The electrons follow the magnetic field lines to the electron collector 490 and the ions pass through the magnetic cusp 486 where the ion trajectory changes to a helical path substantially along the length of the ICC 420. As the ion spirals pass through the electrode 494, which is connected to a resonant circuit (not shown), energy is removed from them. The loss of vertical energy is greatest for the most energetic ions that initially circulate near electrode 494, where the electric field is strongest.

These ionsWith approximately equal initial total energy iReaches magnetic cusp 486. When the ion reaches magnetic cusp 486, there is an ion energy and an ion initial radius r₀Distribution of (2). However, the initial radius r₀Tending to approximate the initial velocity v₀And (4) in proportion. The radial magnetic field and the radial beam velocity generate a lorentz force in the azimuthal direction. The magnetic field at cusp 486 does not change the particle energy, but rather the initial axial velocityConversion into residual axial velocity v_zAnd azimuth velocityIn this case, the first and second substrates,. Azimuth velocityCan be determined from the regular conservation of momentum

In that、、Andin time, the beam ions enter the left side of the cusp 486. In that、、Andwhen it appears to the right of cusp 486

Wherein the content of the first and second substances,is the cyclotron frequency. The rotational frequency of the ions is about 1-10 MHz, preferably about 5-10 MHz, which is the frequency at which power generation occurs.

In order for the ions to pass through the cusp 486, the effective ion radius of gyration must be greater than the cusp 486 at radius r₀The width of (d). It is quite experimentally feasible to reduce the axial velocity to 1/10 so that the residual axial energy will be reduced to 1/100. Then 99% of the ion energy will be converted into rotational energy. The ion beam having v₀And r₀A distribution of values. However, because r₀And v₀Proportionally, as previously indicated by the performance of FRC-based reactors, the efficiency of conversion to rotational energy will be 99% for all ions.

As depicted on fig. 22B, the symmetric electrode structure of the ICC 420 of the present invention preferably includes 4 electrodes 494. An oscillating circuit (not shown) is connected to the electrode structure 494 such that the instantaneous voltages and electric fields are as shown. Voltage and energy storage circuit andfrequency of (2)And (6) oscillating. The azimuthal electric field E at the slot 497 is illustrated in fig. 22B and 25. FIG. 25 illustrates the electric field and ion angular velocity in the gap 497 between the electrodes 494The field it experiences as it rotates. It is evident that in one complete rotation the particles will alternately undergo acceleration and deceleration in an order determined by the initial phase. Except for the azimuthal electric fieldIn addition, there is also a radial electric field. Azimuthal electric fieldIs largest at the gap 497 and decreases as the radius decreases. Fig. 22 assumes that the particles remain rotated with a constant radius. Deceleration will always exceed acceleration because of the gradient in the electric field. The acceleration phase causes the ion radius to increase so that the next time the ion encounters the decelerating electric field, the ion radius will be larger. The deceleration phase will dominate regardless of the initial phase of the ions, due to the azimuthal electric fieldIs always positive. Therefore, the energy conversion efficiency is not limited to 50% caused by the initial phase problem associated with the conventional cyclotron. Electric fieldIs also important. It also oscillates and produces a net effect in the radial direction that returns the beam trajectory to the original radius with zero velocity in the plane perpendicular to the axis as in fig. 22C.

The process by which ions are always decelerated is similar to the strong focusing principle, which is an essential feature of modern accelerators, as described in us patent No. 2736799. If the magnetic field has a positive gradient, the combination of positive (focusing) and negative (defocusing) lenses is positive. A strongly focusing quadrupole doublet is illustrated in fig. 26. The first lens is focused in the x-direction and defocused in the y-direction. The second lens is similar, but the x and y properties are interchanged. The magnetic field is vanished on the symmetry axis and has a positive radial gradient. The net result is a focus in all directions for the ion beam passing through both lenses, regardless of the order of passage.

For penetration including strong axial magnetic field and working at TE₁₁₁Similar results were reported for beams of modal resonators (see Yoshikawa et al). This device is called a "paratron" (japanese fast-wave simple harmonic motion microwave amplifier). In TE₁₁₁In mode, the resonant cavity has a standing wave in which the electric field has quadrupole symmetry. These results are similar in nature to some of the results described herein. There is a difference in the number: the resonator size is much larger (10 meters length) and operates at much higher frequencies (155 MHz) and magnetic fields (10T). Extracting energy from high frequency waves requires a rectenna. The energy spectrum of the beam reduces the conversion efficiency. The presence of two ions is a more serious problem, but the conversion efficiency is on D-He producing 15 MeV protons³A reactor is sufficient.

A single particle trajectory 422 for one particle within ICC 420 is illustrated on fig. 22C. This result was obtained by computer simulation, and the same result was obtained for the peniotron. At a certain radius r₀The incoming ions spiral along the length of the ICC and converge to the same radius r after losing the initial rotational energy₀A point on the circle of (a). The initial condition is asymmetric; the final state reflects this asymmetry, but it is independent of the initial phase. Therefore, all particles are decelerated. The beam at the ion collector end of the ICC is again circular and of similar size. The axial velocity will decrease to 1/10 with a corresponding increase in density. For a single particle, an extraction efficiency of 99% is realistic. However, various factors, such as the vertical rotational energy of the annular beam prior to entering the converter, can reduce this efficiency by about 5%. The electrical power extraction will be at about 1-10 MHz, preferably about 5-10 MHz, for connection to the gridCauses an additional reduction in conversion efficiency.

As shown in fig. 23A and 23B, an embodiment of an electrode structure 494 in an alternative ICC 420 can include two symmetrical semicircular electrodes and/or a tapered electrode 494 that tapers toward the ion collector.

The adjustment of ion dynamics within the main magnetic field of the ICC 420 can be accomplished with two sets of auxiliary coils 500 and 510, as shown in fig. 27A and 24B. Both coil sets 500 and 510 contain adjacent conductors with currents in opposite directions so that the magnetic field has a small range. As schematically shown in fig. 27A, the magnetic field gradient will change the ion rotation frequency and phase. As schematically shown on fig. 27B, the multipole magnetic field will produce bunching, as in a linear accelerator.

Reactor with a reactor core

Figure 28 illustrates a 100 megawatt reactor. The cut-out generator shows a fusion power core region with superconducting coils applying a uniform magnetic field and flux coils for forming a magnetic field with a field-reversal topology. Adjacent to the opposite end of the fusion power core is an ICC energy converter for direct conversion of the kinetic energy of the fusion products into electrical energy. Fig. 29 illustrates a support apparatus for such a reactor.

Propulsion system

Exploration of the solar system (and beyond) requires propulsion capabilities that far exceed the best chemical or electric propulsion systems available. For advanced propulsion applications, the present invention has the greatest promise: design simplicity, high thrust, high specific impulse, high specific power density, low system mass, and little radioactive fuel.

The plasma thrust propulsion system according to the present invention utilizes the high kinetic energy that is trapped in the fusion products as they are axially expelled from the fusion plasma core. Fig. 30 and 31 schematically illustrate a system 800. The system includes an FRC power core 836 impinging beam fusion reactor as described above, including a fusion fuel core 835. The reactor also includes a magnetic field generator 825, a current coil (not shown), and an ion beam implanter 840. An ICC direct energy converter 820, as described above, is coupled to one end of power core 836 and intercepts approximately half of the fusion product particles emerging from both ends of power core 836 in a ring beam 837. As described above, the ICC 820 decelerates them through an inverse cyclotron process and converts their kinetic energy into electrical energy. Magnetic nozzle 850 is positioned adjacent the other end of power core 836 and directs the residual fusion product particles into space as a thrust force T. An annular beam 837 of fusion products flows from one end of fusion power core 836 along field lines 837 into ICC 820 for energy conversion and from the other end of power core 836 along field lines 837 out of nozzle 850 for thrust T.

Bremsstrahlung is converted to electrical energy by Thermoelectric Energy Converter (TEC) 870. Bremsstrahlung energy that is not converted by the TEC 870 is transferred to the Brayton cycle heat engine 880. The waste heat is discharged into the space. The power control subsystem (810, see figure 32) monitors all sources and receivers of electrical and thermal energy (sink) to maintain the system in steady state operation and to provide a separate source of energy (i.e., fuel cell, battery, etc.) to initiate operation of the space craft and propulsion system from a non-operational state. Since the fusion products are chargedParticles, the system does not require the use of massive radiation and neutron shielding, and is therefore characterized by a significant reduction in system mass compared to other nuclear space propulsion systems.

For 100 MW p-B with design as depicted on FIG. 31¹¹The performance of the fusion core example, plasma thrust propulsion system 800 is characterized by the following kinetic parameters:

specific impulse 1.4s

Thrust power 50.8 MW

Thrust power/total output power 0.51

Thrust force 28.1N

Thrust/total output power 281 mN/MW

The system 800 exhibits a high specific impulse that provides for a high ultimate velocity of the space ship utilizing a plasma thrust propulsion system.

A key mission performance/limit metric for all spacecraft is system quality. The major mass components in the plasma thrust propulsion system 800 are illustrated in fig. 31 and 32. For steady state operation, the fusion core 835 requires approximately 50 MW of injected power. The system generates approximately 77 MW of nuclear (particle) power, half of which is recovered in the direct energy converter 820 with up to 90% efficiency. Therefore, an additional 11.5 MW is required to sustain the reactor, this power being supplied by TEC 870 and Brayton heat engine 880.

The primary source of heat in the plasma thruster propulsion system 880 is caused by bremsstrahlung. TEC 870 recovers about 20% of the radiation, i.e., 4.6 MW, delivering about 18.2 MW to a closed-cycle Brayton heat engine 880. Brayton heat engine 880 includes heat exchanger 860, turbine generator, compressor 882 and radiator 886 as shown on fig. 31. The Brayton engine 880 supplies the remaining 7 MW of power needed to sustain the reactor, and another 11 MW is discharged directly into space via a radiator.

The closed-cycle Brayton heat engine is the mature and efficient option for converting the excess heat rejected by TEC 870. In a Brayton engine, the temperature of the maximum cycle is limited by material considerations, which limit the maximum thermodynamic cycle efficiency. From the standard performance map of the Brayton engine, several design points can be extracted. Typical efficiencies can reach as high as 60%. For the present case, 7 MW is required to be recovered, so only 40% efficiency in converting waste heat is acceptable, which is within the limits of the conventional Brayton engines currently available.

The component mass (minus radiator) of the entire Brayton engine was calculated according to the typical specific mass parameter of advanced industrial technology, i.e. in the range of 3 kg/kWe. Turbo-machinery (including compressor, power turbine and recuperator) together 18 MT total subsystem mass.

The heat sink mass is estimated to be 6 MT and heat pipe plates with state of the art high thermal conductivity are preferably used.

Significant system weight also comes from the magnet 825 confining the plasma core 835. Superconducting magnet coils 825 are preferably made of Nb3Sn, which operates stably at 4.5K and a magnetic field of 12.5-13.5T. Nb3Sn requires less stringent low temperatures than other materials considered. With a magnetic field requirement of 7 tesla and a device length of about 7.5 meters, the coil requires 1500 turns of wire carrying 56 kA current. Using 0.5cm radius wire, the total mass of the coil is about 3097 kg. The liquid helium cooling system consists of two pumps, one at each end of the primary coil. The total mass of these pumps is about 60 Kg. The outer structural shell supports the magnet and all internal components from the outside. It is made of kevlar/carbon-carbon composite material 0.01 m thick, with a total mass of about 772 kg. The outermost layer is an insulating cover that shields the interior from temperature changes in the space, estimated at 643 kg. Therefore, for the magnet subsystem 825, the total mass is about 4.8 MT.

Currently, the most suitable ion implantation system for space applications is the induction linac or RFQ. Approximately 15 years ago, RFQ was flying on a scientific probe rocket and successfully demonstrated the use of high voltage power and implantation of an ion beam into space. In a preferred embodiment, 6 implanters 840 are distributed along the length of the CBFR, 3 for each ion. Each injector 840 is preferably a 30-beam dump (beamlet) RFQ having an overall dimension of 0.3 meters long and 0.020 meters radius. Each injector requires an ion source, preferably 0.02 meters long and 0.020 meters radius, to supply ionized hydrogen or boron. One source is required for each accelerator. Both the injector and the source are quite within the currently available range, and their total mass (including source and accelerator) should be about 60 kg with space design improvements.

A conical ICC direct energy converter 820, preferably made of stainless steel, is located at one end of the reactor 836. With a base radius of 0.5 m and a length of 2 m, the ICC mass is approximately 1690 kg. An RF power supply 820 (inverter/converter) recovers (recover) the directed ion stream and converts it to electrical power. The power supply has a mass of about 30 kg. Battery 812 is used to start/restart CBFR. The storage capacity is about 30 MJ. Its mass is about 500 kg. Alternatively, a fuel cell can be used. Additional control means enable the cooperation of all components. The control subsystem mass is estimated to be 30 kg. Therefore, the total energy converter/starter subsystem mass is estimated at about 2.25 MT.

Magnetic nozzle 850 is located at the other end of fusion core 835. Nozzle 850 focuses the fusion product stream into a directed particle stream. It is estimated that the mass of the magnetic nozzle and ICC are about equal because both are composed of superconducting magnets and relatively low mass structural components.

TEC 870 recovers energy from the electromagnetic emissions of the fusion core. It is preferably a thin film structure made of boron-carbon/silicon-germanium with a thickness of 0.02cm, havingAbout 5 g/cm³Mass density of (2). The TEC 870 is located at a first wall, preferably lining the inner surface of the reactor core completely. The mass of the TEC 870 is estimated at about 400 kg. The radiation flux to the TEC 870 was 1.2 MW/cm²Its peak operating temperature is assumed to be less than 1800K。

Thus, the total plasma thruster propulsion system mass is estimated at about 33 MT. This defines the remaining critical task (mission-critical) parameters for the currently discussed 100 MW devices:

total mass/total power 0.33x10^-3 kg/W

Thrust/mass 0.85x10^-3 N/ kg

While the invention is susceptible to various modifications and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms disclosed, but to the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the appended claims.

Claims (53)

1. A plasma generation system includes

A bribery ring, and

a laval nozzle coupled to the bribery ring.

2. The plasma generation system of claim 1, wherein the bribing coil comprises an annular disk-shaped body and a parallel wound coil attached to a face of the body.

3. The plasma generating system of claim 2 wherein the coil is a single turn coil.

4. The plasma generating system of claim 3 wherein the coil is a multi-strand coil.

5. The plasma generating system of claim 3 wherein the wire of said coil begins adjacent an outer diameter of said body at angularly spaced points, turns around said face of said body, and ends at an inner diameter of said body.

6. The plasma generating system of claim 5, wherein the line of coils begins at a perimeter of the body.

7. The plasma generating system of claim 2, wherein said body comprises a hub forming an inner diameter of said body.

8. The plasma generating system of claim 7, wherein the Laval nozzle comprises an annular disk-shaped nozzle arm coupled to the hub.

9. The plasma generating system of claim 8, wherein a face of said arm facing said hub forms an annular gas header and a convergent-divergent nozzle with the face of the hub.

10. The plasma generating system of claim 9, further comprising a plurality of gas passages formed in said hub and communicating with said gas header.

11. The plasma generating system of claim 10, further comprising a valve seat ring having a plurality of valve seats aligned with the plurality of gas passages.

12. The plasma generating system of claim 2, further comprising a sleeve coupled to the body.

13. A method of generating a plasma, comprising the steps of:

distributing the neutral gas over the coils of the parallel winding of the low inductance bribing coil;

exciting the coil winding; and

the gas is ionized into a plasma.

14. The method of claim 13, further comprising the step of ejecting the formed plasma from the briberband.

15. The method of claim 13, wherein the step of energizing the coil comprises energizing all of the wires of the coil.

16. The method of claim 13, wherein the step of energizing the coil comprises energizing a first set of wires, and energizing a second set of wires after a predetermined amount of time.

17. The method of claim 14, wherein the step of injecting a plasma comprises injecting a toroidal plasma.

18. A plasma power generation system includes

A chamber having a main axis;

a first magnetic field generator for generating an azimuthally symmetric magnetic field in a central region of the chamber, the magnetic field having a flux substantially parallel to a major axis of the chamber;

a plasma generator comprising a Laval nozzle and a bribery ring disposed within the chamber; and

a current carrying coil concentric with the chamber major axis for generating an azimuthal electric field within the chamber.

19. The system of claim 18, wherein the chamber comprises

A cylindrical chamber having a first end and a second end; and

a plurality of interruptions extending axially along the chamber wall between and spaced from the first and second ends.

20. The system of claim 18, wherein the bribing coil comprises an annular disk-shaped body and a co-wound coil attached to a face of the body.

21. The system of claim 20, wherein the coil is a single turn coil.

22. The system of claim 21, wherein the wires of the coil begin at an outer diameter of the body, make one turn around the face of the body, and end at an inner diameter of the body at angularly spaced points.

23. The system of claim 22, wherein the lines of coils begin at a perimeter of the body.

24. The system of claim 20, wherein the body comprises a hub forming an inner diameter of the body.

25. The system of claim 24, wherein the laval nozzle includes an annular disk shaped nozzle arm coupled to the hub.

26. The system of claim 25, wherein the faces of the arms facing the hub form an annular gas header and a convergent-divergent nozzle with a hub face.

27. The system of claim 26, further comprising a plurality of gas passages formed in the hub and in communication with the gas header.

28. The system of claim 27, further comprising a valve seat ring having a plurality of valve seats aligned with the plurality of gas passages.

29. The system of claim 20, further comprising a sleeve coupled to the body.

30. The system of claim 18, further comprising a power conversion system within the chamber.

31. The system of claim 30 wherein the power conversion system comprises a plurality of semi-cylindrical electrodes forming a cylindrical surface at the first end region of the chamber.

32. The system of claim 31, wherein the plurality of electrodes comprises more than two electrodes that are spaced apart and form a gap between adjacent electrodes.

33. The system of claim 32, further comprising

A second magnetic field generator for generating an azimuthally symmetric magnetic field having a flux substantially parallel to the chamber major axis in a first end region of the chamber;

an electron collector interposed between the first magnetic field generator and the second magnetic field generator and adjacent to the first ends of the plurality of electrodes; and

an ion collector disposed adjacent to the second ends of the plurality of electrodes.

34. The system of claim 33, further comprising

A second plurality of semi-cylindrical electrodes forming a cylindrical surface at a second end region of the chamber, wherein the second plurality of semi-cylindrical electrodes comprises more than two electrodes spaced apart and forming a gap between adjacent electrodes;

a third magnetic field generator for generating an azimuthally symmetric magnetic field having a flux substantially parallel to the chamber major axis in a region of the second end of the chamber;

a second electron collector interposed between the first magnetic field generator and the third magnetic field generator and adjacent to the first ends of the second plurality of electrodes; and

a second ion collector disposed adjacent to second ends of the second plurality of electrodes.

35. The system of claim 34, further comprising an ion beam implanter coupled to the container.

36. The system of claim 35 wherein the ion beam implanter includes means for neutralizing charge of the ion beam emitted from the implanter.

37. A method for forming a field-reversing configuration magnetic field in a chamber, comprising the steps of:

generating a magnetic guide field in a room;

dispersing a neutral gas over a wound coil of a low inductance briberbed;

a coil winding that excites the bribery ring;

ionizing the gas into a plasma;

injecting a plasma formed from the briberband into the chamber along field lines of the guiding field;

generating an azimuthal electric field in the chamber to rotate the plasma and form a polar magnetic self-field around the plasma;

increasing the rotational energy of the plasma to increase the magnitude of the self-field to a level that overcomes the magnitude of the guiding field; and

the field lines of the guided field and the field lines of the self-field are joined in a magnetic field having a Field Reversed Configuration (FRC) topology.

38. The method of claim 37, wherein the step of energizing the coil comprises energizing all of the wires of the coil.

39. The method of claim 37, wherein the step of energizing the coil comprises energizing a first set of wires, and energizing a second set of wires after a predetermined amount of time.

40. The method of claim 38, wherein the step of injecting a plasma comprises injecting a toroidal plasma.

41. The method of claim 37 wherein the step of generating a guidance field comprises exciting a plurality of field coils and a mirror coil extending around the chamber.

42. The method of claim 37, further comprising the steps of: the magnitude of the guiding field is increased to maintain the rotating plasma at a predetermined radial dimension.

43. The method of claim 37, wherein the step of generating an azimuthal electric field comprises the steps of: exciting an electromagnetic induction accelerator flux coil within the chamber and increasing the current flowing through the coil.

44. The method of claim 43 wherein the step of increasing the rotational energy of the rotating plasma comprises increasing the rate of change of current flowing through the coil.

45. The method of claim 44, further comprising the step of: the rate of change of the current flowing through the flux coil is increased to accelerate the rotating plasma to the rotational energy of the fusion level.

46. The method of claim 37, further comprising the step of creating an electrostatic trap within said chamber.

47. The method of claim 46, further comprising the step of tuning the electrostatic trap.

48. The method of claim 47, wherein the step of tuning the electrostatic trap comprises manipulating an amplitude of the guiding field.

49. The method of claim 45, further comprising the step of: an ion beam having fusion-level energy is injected into the FRC and trapped in the beam on the electromagnetic induction accelerator orbit within the FRC.

50. The method of claim 49, wherein the step of implanting and trapping an ion beam further comprises the steps of:

neutralizing the ion beam;

extracting polarization from the neutralized ion beam; and

lorentz forces due to the applied magnetic field are applied to the neutralized ion beam to bend the ion beam onto the electromagnetic induction accelerator trajectory.

51. The method of claim 49, further comprising the step of: the ions are magnetically confined in the FRC and the electrons are confined in the electrostatic trap.

52. The method of claim 51, further comprising the step of forming fusion product ions.

53. The method of claim 52, further comprising the step of ejecting fusion product ions from the FRC in the form of an annular beam.