RU73405U1 - DEVICE FOR CREATING AN ADJUSTABLE THROUGH POWER IN AN ELECTRIC ION ENGINE - Google Patents

Abstract

The utility model relates to technology, in particular to electric ion engines.

Technical result: in comparison with the analogue, the speed of the ion flow increases, approximately 1.2-1.5 times, which also implies an increase in the traction force of the apparatus. The use of high-frequency modulation of the ion flux allows not only to increase the ion velocity, but also to smoothly change its value.

A device for creating an adjustable traction force in an electric ion engine includes a gas discharge chamber, accelerating and braking voltage sources connected to elements of a multipath ion-optical system, which are three consecutively spaced apart electrodes: a screen, which is the end wall of the gas-discharge chamber accelerating and decelerating. All electrodes have openings for the passage of individual ion beams. The following are additionally introduced into the device: a control electrode located between the accelerating and screen electrodes at a distance d ₁ from the latter and having openings whose centers coincide with the centers of the openings for the passage of individual ion beams; constant voltage source; two resonant circuits. Input parallel resonant circuit, connected between the screen and control electrodes. An output parallel resonant circuit is connected between the accelerating and decelerating electrodes located at a distance d ₂ from each other. An additional generator of high-frequency oscillations, an attenuator, a phase shifter, communication coils and two

high-frequency communication lines through which a high-frequency oscillation generator is connected to both resonant circuits. The attenuator is included in the communication line with the input parallel resonant circuit. Phaser is included in the communication line with the output parallel resonant circuit. The choice of values of the parameters of the device is subject to the relations:

;

,

Where - wavelength of high-frequency oscillations, m;

d ₁ - the distance between the control and the screen electrodes, m;

d ₂ - the distance between the accelerating and slowing electrodes, m;

U ₁ - constant potential difference between the screen and the control electrodes, V;

U ₂ is the potential difference between the screen and accelerating electrodes, V;

To _deputy = U ₃ / U ₂ - the deceleration coefficient, determined by the ratio of the constant voltage on the decelerating electrode - U ₃ to the constant voltage on the accelerating electrode - U ₂ ;

M _i is the relative mass of ions in amu;

U _m1 - the amplitude of the high-frequency voltage between the control and the screen electrodes, V.

1. ill.

Description

The utility model relates to technology, in particular to electric ion engines.

Known ion engine [copyright certificate SU No. 682150], containing a gas discharge chamber and a multipath ion-optical system formed by accelerating and slowing electrodes in which a large number of coaxial holes are made.

A device is also known for creating an adjustable traction force in an electric ion engine [US patent No. 483802], comprising a gas discharge chamber and an ion-optical system formed by two electrodes (screen and accelerating), between which a constant accelerating potential difference is applied.

However, the implementation of this device requires a bulky electric energy storage device (usually a large capacitor bank), as well as a complex switching unit for exciting a pulsed discharge, which includes a microcontroller.

There is also known a method of forming a perforated non-planar electrode, an ion-optical system and an ion thruster [patent for invention Ru No. 2153187], comprising a gas discharge chamber and an ion-optical system consisting of at least three closely spaced electrodes, called screen electrodes, accelerating and decelerating grids. These grids form a periodic structure of the sets of holes, and each set of holes includes one hole of each of the three grids. The disadvantage of the analogue is the high erosion of the accelerator grid, determined by the high energy of the ions, which they gain when passing through the accelerating gap between the screen and accelerating grids.

The closest analogue is a device for accelerating the flow of charged particles [patent for invention RU No. 2104411] containing a plasma source (gas discharge chamber) and a multipath ion-optical system having at least three electrodes in series located at a distance from each other, and the first electrode (screen) is the end wall of the gas discharge chamber and is positively charged. The second accelerating electrode is negatively charged. To improve the structure of the ion flux, after the accelerating electrode, a third slowing electrode is installed, which slows down the fastest ions. The formation of a multipath flux is due to the fact that the electrodes of the ion-optical system have a set of separate coaxial holes for the passage of individual ion beams.

The disadvantages of the closest analogue are that in order to achieve a high speed of the ion stream in the accelerating system, it is necessary to maintain a high accelerating voltage (30-50 kV), which is associated with the danger of electrical breakdown in the insulation elements separating the electrodes or directly in the working gap.

In addition, to smoothly control the speed of the ion stream, it is necessary to introduce special control circuits for the magnitude of the accelerating voltage into the accelerating voltage source, made, for example, on thyristors. This forces to increase the power of the engine power source and leads to an increase in the dimensions and mass of the entire device.

The objective of the claimed utility model is to create a device characterized by a high and smoothly adjustable speed of the ion flux at a reduced accelerating voltage, and this reduces the risk of electrical breakdown between the electrodes of a multipath ion-optical system, reduces the power of the accelerating voltage source, the mass and dimensions of the engine.

The essence of the claimed utility model lies in the fact that the device contains a gas discharge chamber, sources of accelerating and braking voltage, connected to elements of a multipath ion-optical system, which are three consecutively spaced apart electrodes: a screen, which is the end wall of the gas-discharge chamber, accelerating and retarding, having openings for the passage of individual ion beams; a control electrode is additionally introduced into the device, located between the accelerating and screen electrodes at a distance d ₁ from the latter and having openings whose centers coincide with the centers of the openings for the passage of individual ion beams; constant voltage source; two resonant circuits: an input parallel resonant circuit connected between the screen and control electrodes, and an output parallel resonant circuit included between the accelerating and decelerating electrodes located at a distance d ₂ from each other; high-frequency oscillation generator; communication coils and two high-frequency communication lines through which a high-frequency generator

oscillations connected to both resonant circuits; an attenuator included in the communication line with the input parallel resonant circuit; a phase shifter included in the communication line with the output parallel resonant circuit; and the values of the parameters of the device are subject to the relations:

,

,

Where - wavelength of high-frequency oscillations, m;

d ₁ - the distance between the control and the screen electrodes, m;

d ₂ - the distance between the accelerating and slowing electrodes, m;

U ₁ - constant potential difference between the screen and the control electrodes, V;

U ₂ - constant potential difference between the screen and accelerating electrodes, V;

To _deputy = U ₃ / U ₂ - the deceleration coefficient, determined by the ratio of the constant voltage on the decelerating electrode - U ₃ to the constant voltage on the accelerating electrode - U ₂ ;

M _i is the relative mass of ions, expressed in atomic units of mass (amu);

U _m1 - the amplitude of the high-frequency voltage between the control and the screen electrodes, V.

The technical result of the claimed utility model consists in solving the problem posed earlier, namely, achieving a high and smoothly adjustable speed of the ion stream in the accelerating system with reduced, compared with the prototype, values of the accelerating voltage, as well as the dimensions and weight of the entire apparatus.

This is ensured by additional ion acceleration by a high-frequency field at the output of the accelerating system, which

This is achieved by preliminary high-frequency modulation of the ions by density (in the region adjacent to the screen electrode) and their subsequent acceleration in a strong high-frequency field in the gap between the accelerating and slowing electrodes. To do this, between the accelerating and screen electrodes at a distance d ₁ from the screen electrodes, an additional control electrode with holes is introduced, coaxial holes of the electrodes of the multipath ion-optical system, an input parallel resonant circuit is connected between the screen and control electrodes, and an output parallel resonant circuit between the accelerating and slowing electrodes circuit.

The inventive utility model is illustrated using figure 1, which shows a diagram of a device for creating an adjustable traction in an electric ion engine.

In figure 1, the positions 1-20 are indicated:

1 - gas discharge chamber;

2 - screen electrode;

3 - accelerating electrode;

4 - retarding electrode;

5 - holes of the electrodes;

6 - source of accelerating voltage;

7 - source of braking voltage;

8 - control electrode;

9 - holes of the control electrode;

10 - input parallel resonant circuit;

11 - a constant voltage source;

12 - output parallel resonant circuit;

13 - the first round of communication;

14 - second round of communication;

15 - the first high-frequency line;

16 - the second high-frequency line;

17 - generator of high-frequency oscillations;

18 - attenuator;

19 - phase shifter;

20 - thermionic source.

The inventive device comprises a gas discharge chamber 1 for ionizing the working gas, a multipath ion-optical system, which is three electrodes sequentially located at a distance from each other: a screen electrode 2, which is the end wall of the gas discharge chamber 1, accelerating 3 and slowing down 4 electrodes.

All three electrodes are made with coaxial holes 5, for the passage of individual ion beams. Accelerating 6 and decelerating 7 voltage sources are connected to the elements of the multipath ion-optical system. Between the screen 2 and the accelerating 3 electrodes at a distance of d ₁ from the screen electrode, a control electrode 8 is installed, having holes 9 coaxial with the holes 5 of the electrodes 2, 3, 4.

An input parallel resonant circuit 10 is connected between the screen electrodes 2 and the control 8, to which a constant voltage source 11 is connected. Between the accelerating 3 and slowing 4 electrodes installed at a distance d ₂ from each other, the output parallel resonant circuit 12 is connected.

Both resonant circuits 10, 12 are connected by means of communication coils 13, 14 and two high-frequency communication lines 15, 16 with a high-frequency oscillation generator 17.

An attenuator 18 is connected in the communication line with the input parallel resonant circuit 10, and a phase shifter 19 is connected in the communication line with the output parallel resonant circuit 19. A thermionic source 20 is installed at the motor output.

A device for creating an adjustable traction in an electric ion engine operates as follows. Customize

both parallel resonant circuits 10, 12 to one resonant frequency and after initiating a discharge in the gas discharge chamber 1 and applying a negative bias voltage between the screen 2 and the control 8 electrodes from the constant voltage power supply 11, as well as the constant voltage to the accelerating and slowing electrodes from the accelerating source voltage 6 and the source of braking voltage 7, respectively, excite the input parallel resonant circuit 10 with a small part of the high-frequency power from the generator frequency oscillations 17, equipped with devices for regulating the amplitude and phase of the output signal. Most of the output power of the high-frequency oscillation generator 17 is supplied to the output parallel resonant circuit 12, and the phase of the high-frequency voltage acting between the accelerating 3 and slowing 4 electrodes is selected using the phase shifter 19 so that it coincides with the phase of the ion clusters in the grouped multipath ion stream. Moreover, the wavelength of the generator of high-frequency oscillations 17 is selected from the following conditions:

Where - wavelength of high-frequency oscillations, m;

U ₂ is the potential difference between the screen and accelerating electrodes, V;

To _deputy = U ₃ / U ₂ - the deceleration coefficient, determined by the ratio of the constant voltage on the decelerating electrode - U ₃ to the constant voltage on the accelerating electrode - U ₂ ;

M _i is the relative mass of ions in amu;

d ₂ - the distance between the accelerating and slowing electrodes, m

At a wavelength shorter than that indicated in relation (1), the efficiency of the interaction of ions with a high-frequency field in the output gap decreases due to the manifestation of the inertia effect. It leads to

a decrease in the ion flux velocity, as well as in linear ion accelerators.

The traction force is smoothly regulated using the attenuator 18, changing the magnitude of the amplitude of the high-frequency voltage U _m1 acting between the control 8 and the screen 2 electrodes, choosing it from the condition:

, (2)

Installed at the engine output, a thermionic source 20 provides neutralization of the space charge of the ion flux.

The implementation of the proposed device is illustrated by the following examples:

Example No. 1.

We calculate the distance d ₁ between the screen and control electrodes according to the proposed ratio:

Let us take as an example the following parameters typical for a multipath ion engine operating on xenon ions (Xe):

M = 131.29 a.m.

d ₂ = 5 m

U ₂ = 5000 B,

To _deputy = 0.7.

U ₁ = 2500 V.

U _m1 / U ₁ = 0.5.

From above, the value of d ₁ for the selected parameters is limited by the condition:

m

From below, the value of d _{1 min is} limited by the condition for the occurrence of electrical breakdown. The maximum electric field strength at a distance between the screen and control electrodes d _{1 min} can be approximately determined by the formula:

V / m

From this ratio we determine d _{1 min} , substituting the given parameters into it:

U ₁ = 2500 V.

U _m1 / U ₁ = 0.5.

m

Example No. 2.

We calculate the wavelength of the generator of high-frequency oscillations, according to the proposed formula:

(one)

We take as the initial data the parameters of example No. 1. M = 131.29 a.m., d ₂ = 5 · 10 ^-3 m, U ₂ = 5000 V, K _deputy = 0.7.

After substituting these parameters in formula (1), we obtain restrictive conditions for choosing a wavelength at which the efficiency of converting the energy of high-frequency vibrations into ion flux energy is high:

m

Passing from the wavelength to the operating frequency, we have

F = 300 / 2.506 MHz.

At higher frequencies, the effect of inertia of ions is manifested and the efficiency of the device decreases.

m

Example No. 3

We determine the speed of ions at the output of the ion engine. In the case of plane-parallel electrodes located at a distance d ₂ from each other and under potentials U ₂ and U ₃ + U _m2 ^* cos ( t), the ion velocity can be calculated by the formula:

,

where U _m2 is the amplitude of the high-frequency voltage acting between the accelerating and slowing electrodes, M _i is the mass of ions.

This formula can be rewritten as:

,

Where = U _m2 / U ₃ is the relative amplitude of the high-frequency voltage at the distance between the accelerating and slowing electrodes.

Assuming M = 131.29 amu, = 1, U ₂ = 5000 V, U ₃ = 3500 V, we obtain - V _i = 93.5 km / s.

In the absence of modulation = 0, U ₂ = 5000 V, U ₃ = 3500 V, V _i = 78.73 km / s.

Thus, the introduction at low accelerating voltages (U ₂ , U ₃ ) of high-frequency modulation and acceleration of the ion flux increases the speed of the ion stream at the output of the device, with the selected parameters, by about 1.2 times. To achieve the same result, a prototype would require large accelerating voltages. The speed of the ion flow in the inventive device can be smoothly controlled by changing the amplitude and phase of the modulating high-frequency voltage.

Therefore, the objective of the claimed utility model, which consists in creating a device characterized by a high and smoothly adjustable speed of the ion flux at a reduced accelerating voltage, is fulfilled. At the same time, the risk of electrical breakdown between the electrodes of the multipath ion-optical system and

the power of the accelerating voltage source, the mass and dimensions of the engine can be reduced.

Claims (1)

A device for creating an adjustable traction force in an electric ion engine, comprising a gas discharge chamber, accelerating and braking voltage sources connected to elements of a multi-beam ion-optical system, which are three electrodes sequentially spaced apart from each other and having openings for the passage of individual ion beams, a screen electrode, which is the end wall of the gas discharge chamber, accelerating and slowing down the electrodes, characterized in that the device additionally a control electrode located between the accelerating and shield electrodes at a distance of d ₁ from the last and having holes coaxial with holes for the passage of individual ion beams in the electrodes of a multipath ion-optical system, a constant voltage source, two resonant circuits: an input parallel resonant circuit included between the screen and control electrodes, and the output parallel resonant circuit included between the accelerating and slowing electrodes located at a distance d ₂ each about a friend, a high-frequency oscillation generator, communication coils and two high-frequency communication lines through which a high-frequency oscillation generator is connected to both resonant circuits, an attenuator included in a communication line with an input parallel resonant circuit, a phase shifter included in a communication line with an output parallel resonant circuit, moreover, the values of the parameters of the device are subject to the relations

;

, Where

- wavelength of high-frequency oscillations, m; d ₁ - the distance between the control and the screen electrodes, m; d ₂ - the distance between the accelerating and slowing electrodes, m; U ₁ - constant potential difference between the screen and the control electrodes, V; U ₂ - constant potential difference between the screen and accelerating electrodes, V; To _deputy = U ₃ / U ₂ - the deceleration coefficient, determined by the ratio of the constant voltage on the decelerating electrode - U ₃ to the constant voltage on the accelerating electrode - U ₂ ; M _i is the relative mass of ions, expressed in atomic units of mass (amu); U _m1 - the amplitude of the high-frequency voltage between the control and the screen electrodes, V.