WO2018009983A1

WO2018009983A1 - A brushless electrical machine

Info

Publication number: WO2018009983A1
Application number: PCT/AU2017/050733
Authority: WO
Inventors: Gregory Paxton
Original assignee: Energy Dynamics Technology Ltd
Current assignee: Energy Dynamics Technology Ltd
Priority date: 2016-07-15
Filing date: 2017-07-14
Publication date: 2018-01-18
Anticipated expiration: 2019-01-15
Also published as: TW201817129A

Abstract

A brushless generator (1) includes a cylindrical stator (2) for containing two diametrically opposed first coils (5) and (6), two diametrically opposed second coils (7) and (8), and two diametrically opposed third coils (9) and (10). Coils (5) and (6) are bifilarly wound with coils (7) and (8) respectively, and coils (9) and (10) are connected in respective closed circuits with coils (7) and (8). The generator is an inner rotor type. Four radially spaced apart rare earth permanent magnets (23, 24, 25) and (26) are mounted to core (16) adjacent to periphery (20) with respective south poles being most closely adjacent to surface (21). The rotation of rotor results in movement of the permanent magnets (23, 24, 25) and (26) and produces a voltage across coils (5) and (6). A switching device or a control circuit (35) selectively applies that voltage to an electrical outlet (40).

Description

A BRUSHLESS ELECTRICAL MACHINE

FIELD OF THE IN VENTION

[0001] The present invention relates to an electrical machine and in particular to a brushless electrical machine and a method of using such a machine.

[0002] Embodiments of the invention have been particularly developed as electrical generators and will be described herein with particular reference to that application. However, it will be appreciated that the invention is not limited to such a field of use, and is also applicable in broader contexts such as electrical motors and other electrical machines.

BACKGROUND

[0003] Any discussion of the background art throughout the specification should in no way be considered as an admission that such art is widely known or forms part of common general knowledge in the field.

[0004] Electrical generators are almost ubiquitous and are machines that convert mechanical energy into electric energy. The development of generators has been ongoing for over a century.

[0005] The rotor is a disk or a cylinder, consisting of ceramic or ainico type permanent magnets or coils made from copper wire wound on laminated iron poles. The stator consists of coil windings or magnets or both. When the rotor is rotated, the magnets cause electrical current to flow in the windings, which is then used to power various devices.

[0006] The generally accepted main limitation of modern generators is the relatively low- efficiency of conversion of mechanical energy to electrical energy. For commercially available generators the efficiency is typically less than 50%. This is a result of a number of losses, such as:

• Hysteresis losses, with the conventional approach commonly adopted being the use laminated iron cores for the windings. This results in a relatively expensive and heavy machine.

• Eddy current losses, with the conventional approach commonly adopted being the elimination of as much conductive metal as possible from the machine.

• Magnetic drag, or the back electromagnetic force (back-emf), that is produced in motors and generators.

[0007] Given the widespread use of generators and other electrical machines there is significant cost and environmental advantage to be gained by even a small improvement in operational efficiency. Accordingly, there is a need for an improved electrical machine. SUMMARY OF THE INVENTION

[0008] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative,

[0009] According to a first aspect of the invention there is provided a brashless generator including:

a stator having a plurality of spaced apart first coils, a corresponding plurality of spaced apart second coils, and a corresponding plurality of spaced apart third coils, wherein each first coil is bifiiarly wound with a respective second coil and each third coil is connected in a closed circuit with a respective second coil;

a rotor having:

a rotor core that is mounted for relative rotation with respect to the stator and which has a periphery that, in use, is adjacent to the stator; and a plurality of spaced apart permanent magnets mounted to the rotor core at or adjacent to the periphery;

an input shaft for allowing rotation of the rotor relative to the stator such the movement of at least one of the permanent magnets produces a voltage across at least one of the first coils; and a switching device for receiving the voltage produced across the at least one of the first coils and selectively applying that voltage to an electrical outlet.

[0010] In an embodiment, the electric outlet includes electrical terminals for selectively electrically connecting to an electrical load.

[001 1 ] In an embodiment, the electrical outlet includes an energy storage device disposed between the switching device and the electrical terminals.

[0012] In an embodiment, the energy storage device is a capacitor.

[0013] In an embodiment, the electric outlet includes an inverter disposed between the energy storage device and the terminals for allowing an AC voltage to be produced at the terminals.

[0014] In an embodiment, the permanent magnets are rare-earth magnets.

[0015] In an embodiment, the generator includes an even number of permanent magnets.

[0016] In an embodiment, the permanent magnets are mounted to the core in diametrically opposite pairs.

[0017] In an embodiment, the coils have soft iron cores.

[0018] In an embodiment, the coils are formed substantially from copper windings. [0019] In an embodiment, the generator includes an even number of first, second and third coils.

[0020] In an embodiment, the number of each of the first, second and third coils is an integral multiple of four,

[0021 ] In an embodiment, the generator includes two first coils, two second coils and two third coils.

[0022] In an embodiment, the rotor core is formed substantially from an amorphous metal.

[0023] In an embodiment, the rotor core is formed substantially from at least one amorphous metal.

[0024] in an embodiment, the movement of the at least one of the permanent magnets directly produces a voltage across at least one of the first coils.

[0025] In an embodiment, the movement of the at least one of the permanent magnets indirectly produces a voltage across at least one of the first coils.

[0026] In an embodiment, the movement of the at least one of the permanent magnets directly produces a voltage across at least one of the third coils which, in turn, results in the voltage being produced across at least one of the first coils.

[0027] In an embodiment, the switching device applies the voltage to the electrical outlet such that the resultant current flow reduces the back-electromotive force experienced by the generator.

[0028] In an embodiment, the generator includes a sensor for providing a first signal indicative of the rotational position of the rotor relative to the stator, wherein the switching device is responsive to the signal for selective applying the voltage to the electrical outlet.

[0029] According to a second aspect of the invention there is provided a brushless motor including:

a stator having a plurality of spaced apart first coils, a corresponding plurality of spaced apart second coils, and a corresponding plurality of spaced apart third coils, wherein each first coil is bifilarlv wound with a respective second coil and each third coil is connected in a closed circuit with a respective second coil;

a rotor having:

an input shaft for allowing rotation of the rotor relative to the stator such the movement of at least one of the permanent magnets produces a voltage across at least one of the first coils; and a switching device for selectively energizing the first coils for producing rotation of the rotor relative to the stator.

[0030] According to a third aspect of the invention there is provided a hrushless generator/motor including:

a stator having a first set of coils and a second set of coils, wherein the coils in the sets are alternated with each other;

a rotor having:

a rotor core that is mounted for relative rotation with respect to the stator and which has a periphery that, in use, is adjacent to the stator; and a plurality of spaced apart permanent magnets mounted to the rotor core at or adjacent to the periphery such that during rotation of the core the magnets are simultaneously opposed alternatively to respective coils in the first set and the second set; and

a switching device for selectively energizing and drawing energy from the first set of coils and the second set of coils during relative rotation of the rotor core with respect to the stator.

[0031 ] According to a fourth aspect of the invention there is provided a brushless electrical machine including:

a rotor having:

a rotor core that is mounted for relative rotation with respect to the stator and which has a periphery that, in use, is adjacent to the stator; and a plurality of spaced apart permanent magnets mounted to the rotor core at or adjacent to the periphery; and a switching device for any one or more of: energizing the first coils; drawing energy from the first coils; and electrically isolating the first coils.

[0032] According to a fifth aspect of the invention there is provided a method of generating a voltage, the method including the steps of:

having a plurality of spaced apart first coils disposed about a stator together with a corresponding plurality of spaced apart second coils, and a corresponding plurality of spaced apart third coils, wherein each first coil is bifilarly wound with a respective second coil and each third coil is connected in a closed circuit with a respective second coil;

pro viding a rotor having:

allowing rotation of the rotor relative to the stator such the movement of at least one of the permanent magnets produces a voltage across at least one of the first coils; and

a switching device for receiving the voltage produced across the at least one of the first coils and selectively applying that voltage to an electrical outlet.

[0033] According to a sixth aspect of the invention there is provided a method of generating mechanical rotation, the method including the steps of:

having a plurality of spaced apart first coils disposed on a stator together with a corresponding plurality of spaced apart second coils, and a corresponding plurality of spaced apart third coils, wherein each first coil is bifilarly wound with a respective second coil and each third coil is connected in a closed circuit with a respective second coil;

pro viding a rotor having:

allowing rotation of the rotor relative to the stator such the movement of at least one of the permanent magnets produces a voltage across at least one of the first coils; a switching device for selectively energizing the first coils for producing rotation of the rotor relative to the stator; and

an output shaft for supporting the rotor and for transmitting the rotation of the rotor to a mechanical load.

[0034] According to a seventh aspect of the invention there is provided a method of operating a brushless generator/motor, the method including the steps of:

providing a stator having a first set of coils and a second set of coils, wherein the coils in the sets are alternated with each other;

providing a rotor having:

selectively energizing and drawing energy from the first set of coils and the second set of coils during relative rotation of the rotor core with respect to the stator,

[0035] According to an eighth aspect of the invention there is provided a method of operating a brushless electrical machine, the method including the steps of:

providing a stator having a plurality of spaced apart first coils, a corresponding plurality of spaced apart second coils, and a corresponding plurality of spaced apart third coils, wherein each first coil is bifilailv wound with a respective second coil and each third coil is connected in a closed circuit with a respective second coil;

providing a rotor having:

a rotor core that is mounted for relative rotation with respect to the stator and which has a periphery that, in use, is adjacent to the stator; and a plurality of spaced apart permanent magnets mounted to the rotor core at or adjacent to the periphery; and

performing any one or more of: energizing the first coils; drawing energy from, the first coils; and electrically isolating the first coils. [0036] According to a ninth aspect of the invention there is provided a brushless electrical machine including:

a rotor having:

a rotor core with a periphery; and

a plurality of spaced apart permanent magnets mounted to the rotor core and providing respective magnetic poles adjacent to the periphery; and a stator having a plurality of spaced apart first coils that are connected in parallel and a plurality of spaced apart second coils that are magnetically coupled with respective first coils, wherein the stator receives the rotor to allow for movement between the magnetic poles and the first coils so that one of the following induces the other:

relative rotation between the stator and the rotor; and

a voltage across the second coils.

[0037] In an embodiment the plurality of permanent magnets present the same polarity at the periphery.

[0038] In an embodiment the plurality of permanent magnets present alternate magnetic polarities at the periphery.

[0039] in an embodiment the plurality of permanent magnets includes a number of magnets that is even.

[0040] In an embodiment the number of magnets is an integral multiple of four.

[0041 ] In an embodiment the magnets in the plurality of permanent magnets are equally angularly spaced about the periphery.

[0042] In an embodiment the first coils are each wound around respective cores.

[0043] In an embodiment the second coils are each wound around respective cores shared with a corresponding first coil.

[0044] In an embodiment the first coils include first windings of a common first diameter and the second coils include second windings of a common second diameter.

[0045] In an embodiment the common first diameter is about 0.50 to 0.60 mm.

[0046] In an embodiment the common first diameter is about 0.55 mm.

[0047] In an embodiment the common second diameter is about 0.40 to 0.50 mm.

[0048] In an embodiment the common second diameter is about 0.46 mm. [0049] In an embodiment the common first diameter is greater than the common second diameter.

[0050] In an embodiment the common first diameter is about 18% to 21% greater than the common second diameter.

[0051 ] In an embodiment the first coils are bifiiar.

[0052] In an embodiment the second coils are bifiiar.

[0053] In an embodiment the second coils are connected in parallel to an output.

[0054] In an embodiment the second coils are connected to the output via a rectification circuit.

[0055] In an embodiment the rectification circuit is bidirectional.

[0056] In an embodiment the brushless electrical machine includes a starter circuit.

[0057] In an embodiment the starter circuit includes at least one coil disposed intermediate at least two of the first coils.

[0058] According to a tenth aspect of the invention there is provided a method for operating a brushless electrical machine, the method including the steps of:

providing a rotor having:

a rotor core with a periphery;

a plurality of spaced apart permanent magnets mounted to the rotor core and providing respective magnetic poles adjacent to the periphery; and providing a stator having a plurality of spaced apart first coils that are connected in parallel a plurality of spaced apart second coils that are magnetically coupled with respective first coils, wherein the stator receives the rotor such the periphery rotates past the first coils such that one of the following induces the other:

relative rotation between the stator and the rotor; and

a voltage across the second coils.

[0059] According to an eleventh aspect of the invention there is provided a brushless electrical machine including:

a plurality of substantially parallel plates;

an axle extending substantially normal to and being supported by one or more of the plates; a rotor that is mounted to the axle for rotation relative to the plates, where the rotor includes a circumferential periphery at or adjacent to which are disposed a plurality of spaced apart permanent magnets that generate respective magnetic fields; and a plurality of coil assemblies being supported by one or more of the plates and past which the magnetic fields are selectively moved to transfer energy between the rotor and the assemblies.

[0080] In an embodiment the electrical machine includes n rotors and (n + 1) plates.

[0081 ] In an embodiment the electrical machine includes n rotors, where n > 2, and (n - 1) plates.

[0082] In an embodiment the electrical machine includes n rotors and 2n plates.

[0063] In an embodiment the plates, in use, include opposed faces having respective mounting formations for receiving the coil assemblies.

[0064] In an embodiment, the mounting formations include channels.

[0065] In an embodiment, the channels are machined in the plate.

[0066] In an embodiment the channels extend radially.

[0067] In an embodiment the assemblies are releasably slideably received by the mounting formations for allowing selective radial movement of the assemblies.

[0068] In an embodiment each assembly includes a mounting frame that is received by the mounting formations, at least one coil that is supported by the frame and which is, in use, moveable radially relative to the frame.

[0069] In an embodiment the plates are secured to each other.

[0070] in an embodiment each of the plates includes two opposite faces and a peripheral edge extending between the faces.

[0071 ] In an embodiment, the plates are at least partly secured to each other by one or more of: at least one member that extends between the opposed faces of adjacent plates; and at least one member that extends between the edges of at least two of the plates.

[0072] According to a twelfth aspect of the invention there is provided a method of operating a brushless electrical machine, the method including the steps of:

providing a plurality of substantially parallel plates;

supporting an axle with one or more of the plates, wherein the axle extends substantially normal to the plates; mounting a rotor to the axle for rotation relative to the plates, where the rotor includes a circumferential periphery at or adjacent to which are disposed a plurality of spaced apart permanent magnets that generate respective magnetic fields; and supporting a plurality of coil assemblies by one or more or the plates and selectively moving the fields relative to the assemblies to transfer energy between the rotor and the assemblies.

[0073] Reference throughout this specification to "one embodiment", "some embodiments" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment", "in some embodiments" or "in an embodiment" in various places throughout this specification are not necessarily ail referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

[0074] As used herein, unless otherwise specified the use of the ordinal adjectives "first", "second", "third", etc., to describe a common object, merely indicate that different instances of like or similar objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, in importance or significance or in any other manner.

[0075] As used herein, the term "exemplary" is used in the sense of providing examples, as opposed to indicating quality. That is, an "exemplary embodiment" is an embodiment provided as an example, as opposed to necessarily being an embodiment of exemplary quality.

BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a cross-sectional view of an electrical machine according to one embodiment of the invention;

Figure 2 is an exploded view of the machine of Figure 1 illustrating schematically the electrical connections between the coils;

Figure 3 is a schematic representation of the wiring for a stator of a generator according to a further embodiment of the invention;

Figure 4 is a schematic representation of the wiring for a further generator/motor according to an embodiment of the invention; Figure 5 is a top view of a further embodiment of a brushless electrical machine according to a further embodiment of the invention in the form of a generator having a stator with the wiring illustrated in Figure 3;

Figure 6 is a side view of the machine of figure 5; and

Figure 7 is a top view of one of the assemblies used in the generator of Figure 5.

DETAILED DESCRIPTION

[0077] Referring to Figure 1 there is provided a brushless generator 1 including a generally cylindrical stator 2 having a stator housing 3 for containing, as shown in Figure 2, two diametrically opposed first coils 5 and 6, two diametrically opposed second coils 7 and 8, and two diametrically opposed third coils 9 and 10. Coils 5 and 6 are bifilarly wound with coil 7 and 8 respectively, and coils 9 and 10 are connected in respective closed circuits with coils 7 and 8. A rotor 15 has a generally cylindrical rotor core 16 that is mounted for relative rotation with respect to stator 2 and which has a continuous circumferential periphery 20 that, in use, is adjacent to and opposed with a generally cylindrical continuous inner surface 21 of housing 3. Four equally radially spaced apart rare-earth permanent magnets 23, 24, 25 and 26 are mounted to core 1 6 adjacent to periphery 20 with respective south poles being most closely adjacent to surface 21. An input shaft 31 extends along an axis 32 for allowing rotation of rotor 15 about that axis relative to stator 2, such that the consequent movement of at least one of the permanent magnets 23, 24, 25 or 26, produces a voltage across at least one of coils 5 and 6. A switching device, in the form of a control circuit 35, receives the voltage produced across the at least one of coils 5 and 6 and selectively applies that voltage to an electrical outlet 40.

[0078] The shaft 31 is able to be driven mechanically by one of a variety of external sources to produce rotation of rotor 15 relative to stator 3 and hence movement of magnets 23 to 26 relative to coils 5 to 10. For example, in some embodiments, the external source is an internal combustion engine (such as a petrol fuelled engine or a diesel fuelled engine), a wind powered system, a hydroelectric system, or other such source.

[0079] Outlet 40 includes two electrical terminals 41 and 42 for selectively electrically connecting to an electrical load 43. In some embodiments outlet 40 includes an energy storage device such as a battery and/or a capacitor (not shown) and an inverter (not shown) disposed between the circuit 35 and terminals 41 and 43 for allowing the energy obtained from the voltage produced by coils 5 and 6 to be stored and then converted into an AC voltage that is supplied to load 43. In other embodiments outlet 40 includes a buck/boost converter for supplying a DC voltage to load 43. [0080] Magnets 23 to 26 inclusive are all substantially alike rare-earth magnets that are generally cylindrical in shape and each of which has a unitary form. In other embodiments, a plurality of separate magnets is stacked and secured together to form, a single one of magnets 23 to 26.

[0081 ] it will be noted that use is made in this embodiment of four equally circumferentially spaced apart permanent magnets, in that the magnets are mounted to core 16 in diametrically opposite pairs. Preferentially, other embodiments also make use of an even number of equally spaced apart permanent magnets, and more preferably a number of magnets that is an integral multiple of four, in one preferred form., use is made of eight permanent magnets.

[0082] All of coils 5 to 10 are formed of copper wire that is wound around soft iron cores (not shown). As coils 5 and 7 are bifilar, they are wound around a common soft iron core. Similarly, coils 6 and 8 are wound around another common soft iron core that is separate from the other.

[0083] It will be noted that there is an even number of first, second and third coils and, moreover, the number of each of the first, second and third coils is an integral multiple of four.

[0084] Rotor core 16 is formed substantially from an amorphous metal such as amorphous polycrystalline ferrite. In other embodiments, a different amorphous metal, or combination of amorphous metals, is used. Particularly, core 16 includes four equally angularly spaced apart radial diverging amorphous metal members 45, 45, 47 and 48 that extend between first ends that are engaged with shaft 31 and second ends that are engaged with respective magnets 23, 24, 25 and 26. Members 45 to 48 are rigid and generally cylindrical and, in use, maintain the respective magnets 23 to 26 closely adjacent to periphery 20.

[0085] The coils 5 to 10 are configured such that the movement of magnets 23 to 26 directly produces a voltage across at least one of the first coils.

[0086] With relative rotation between rotor 15 and stator 3, the resultant movement of the permanent magnets, when in the vicinity of coils 5 and 6, produces a voltage across those coils. Moreover, the movement of the permanent magnets, when in the vicinity of coils 9 and 10, directly produces a voltage across those coils which, in turn, results in a voltage being produced across coils 5 and 7 respectively (via coils 7 and 8). This interaction is further influenced by control circuit 35 applying the voltage generated across coils 5 and 6 to outlet 40 such that the resultant current flow in coils 5 and 6 reduces the back-electromotive force experienced by generator 1.

[0087] Generator 1 includes a sensor device (not shown) including a plurality of sensors for providing a respective sensor signals indicative of characteristics of operation of the generator. This includes a first signal indicative of the rotational position of rotor 15 relative to stator 3, together with timing information, such that circuit 35 is able to be responsive to the first signal for selective applying the voltage to outlet 40 to allow the back-emf to be minimised.

[0088] It will be appreciated that circuit 35 is a solid state switching circuit that includes many different electronic components that are combined to provide the switching required. In this embodiment use is made of primarily MOSFET devices to provide the switching due to the fast acting and low loss characteristics of these devices. However, in other embodiments bipolar devices, or a combination of bipolar- and MOSFET devices are used. It will also be appreciated that circuit 15 includes a processor for containing software code that is executable to control the MOSFET devices to accurately switch the current supplied to and drawn from, coils 5 and 6 in response to the relevant sensor signals being received.

[0089] The operation of generator 1 is as follows.

[0090] The soft iron metal used in the cores about which coils 5 to 10 are wound exhibit practically zero hysteresis loss, have little or no magnetic memory, and cannot sustain any current flow even though they will polarize magnetically nearly as well as iron and other alloys used for cores. Consequently, the cores do not appreciably heat up during normal operation of generator 1.

[0091 ] The even-number configuration of the magnets in generator 1 provides for a magnetic balance which minimises the work required to rotate the rotor 15 relative to stator 3 despite the bias for the magnets to remain immediately adjacent to the closest stator coil. It has been found that the main losses in rotation of stator 15 are frictional, as provided by the bearings upon which shaft 31 is mounted.

[0092] Circuit 35 turns the stator coils 5 and 6 "on" and "off at the appropriate times to "clip" and channel the current flow through all the coils 5 to 10. This is done to minimise the build up of back-emf in generator 1.

[0093] It has been found that the optimum speed of rotation of rotor 16 is about 2,300 RPM. However, other rotational speeds are available, and speeds in the range of about 1,500 RPM to 3,000 RPM are also suitable.

[0094] In another embodiment, the rotor and stator of generator 1 is configured as a motor, in that load 43 is substituted with an electrical energy source and circuit 35 operates to selectively energise coils 5 and 6 such that shaft 31 is rotated for mechanically supplying rotational energy to an external mechanical load (not shown). That is, circuit 35 selective switches a DC voltage across coils 5 and 6 directly, which results in voltages being produced also in coils 7 to 10. As the voltage is switched, when transitions between both "on" and "off, there are relatively large changes in currents flowing in the coils and, hence, relatively rapidly expanding, or contracting magnetic fields being generated. It will be appreciated that the application of the voltage and current to coils 5 and 6 is carefully timed to repel the magnets from those coils (and indirectly coils 9 and 10 offer the same effect for the other magnets) and create a motive force. The sensor device in this embodiment includes a position sensor to facilitate the correct timing of the energisation and de- energisation of coils 5 and 6 by circuit 35. Examples of such a position sensor include a Hall Effect Sensor, an optical encoder, a special sensing coil.

[0095] When coils 5 and 6 are energised they create respective expanding magnetic fields which repel the adjacent magnet such that rotor 15 is rotated relative to stator 6, and mechanical rotation induced in shaft 31.

[0096] It has been found that the "on" time of the energising pulse supplied to coils 5 and 6 at higher speeds (for example, at 2,300 RPM) becomes very small and the efficiency of generator 1 is optimised as it uses less energy per impulse to maintain the given output of the motor.

[0097] As will be understood by those skilled in the art, the magnetic output of coils 5 and 6 will be dependent upon the size and type of the core material, the number of turns of wire in the coil, the diameter and length of the wire and the material from which it is made, and the temporal characteristics of the current that is applied to the coil.

[0098] In another embodiment there is provided a motor/generator. In this embodiment, the rotor and stator of generator 1 include eight equally spaced apart rare -earth permanent magnets, arranged in two like sets that are equally angularly displaced such that the magnets in each set are alternated about periphery 20 with magnets from the other set. This allows circuit 35 to drive one set of magnets as a generator and the other set as a motor and for that to be done simultaneously, if required. The preferential rotational speed for the motor/generator is 2,300 RPM.

[0099] In an embodiment, the first coils in one of the sets are energised, by circuit 35, with a short pulse of current (2 Amps at 16 V DC) when a magnet is directly adjacent to those first coils. This results in those magnets being repelled and rotation of shaft 31 to occur. When the following magnets are directly adjacent to those same first coils a further energisation of the first coils occurs, and so on. The use of the bifilar configuration allows reclamation of energy that would otherwise be expended in generating a back-emf in the motor.

[00100] The other set of coils are used to draw electrical energy from the motor generator, which is stored in a battery and/or capacitor or other energy storage device.

[00101 ] When the motor function and the generator function are operating simultaneously, this allows for a recovery of energy that may have otherwise been lost during the operation of the motor function only. [00102] As presently postulated by the inventor, the operation of the above motor/generator, at the given speed and with the combination of structures and materials used, gains the benefits of the Schumann Resonance of the earth.

[00103] In an embodiment, there is provided a brushless electrical machine including:

a stator having a plurality of spaced apart first coils, a corresponding plurality of spaced apart second coils, and a corresponding plurality of spaced apart third coils, wherein each first coil is bi.fil.arly wound with a respective second coil and each third coil is connected in a closed circuit with a respective second coil; a rotor having:

a switching device for any one or more of: energizing the first coils; drawing energy from the first coils; electrically isolating the first coils.

[00104] Details of a further embodiment of the invention, in the form of a generator 51, is provided in Figure 3, where corresponding features are denoted by corresponding reference numerals. Generator 51 is a brushless electrical machine including a rotor having a rotor core with a periphery (none of which are explicitly shown) for supporting a plurality of eighty equally angularly spaced apart permanent magnets 52 providing north polarity magnetic poles at the periphery. The stator 2 has a plurality of spaced apart first coils 53 that are connected in simple parallel with each other - that is, there are no intervening active or passive components between the coils, only conductors. A plurality of spaced apart second coils 54 are magnetically coupled with respective first coils 53. Stator 2 receives the rotor to allow for movement between the magnetic poles of magnets 52 and coils 53 so that one of the following induces the other: relative rotation between the stator and the rotor; and a voltage across the second coils.

[00105] As illustrated, magnets 52 present the same polarity at the periphery to facilitate a consistent configuration, and winding of coils 53 and 54. In other embodiments, magnets 52 present alternate magnetic polarities at the periphery and coils 53 and 54 are wound/energised accordingly. The embodiment illustrated in Figure 3 is configured for simplicity of wiring. In other embodiments, for example, where each coil 53 and/or 54 is individually switched, then any predetermined combination or sequence of magnetic polarities provided by magnets 52 at the periphery of the rotor are able to be accommodated. [00108] The plurality of permanent magnets in this embodiment includes a number of magnets that is even, and an integral multiple of four. Moreover, magnets 52 are equally angularly spaced about the periphery.

[00107] Coils 53 are each wound around respective cores (not shown) together with respective coils 54. Coils 53 include first copper windings of a common first diameter of 0.55 mm and coils 54 include second copper windings of a common second diameter of 0.46 mm. Preferentially, the grade of copper used in the windings is common, and the conductive connections between coils 53 is also of the common first diameter.

[00108] In other embodiments, the common first diameter is other than 0.55 mm. It has been found that a preferential common first diameter about 0.50 to 0.60 mm. However, for small electrical machines it is possible to use smaller diameter windings.

[00109] In other embodiments, the common second diameter is other than 0.46 mm. It has been found that a preferential common first diameter about 0.40 to 0.50 mm. However, for small electrical machines it is possible to use smaller diameter windings.

[001 10] It has been found by the inventor that there is advantage in the electric machine of the embodiments wherein the common first diameter is greater than the common second diameter, and more preferentially for the common first diameter to be about 18% to 21 % greater than the common second diameter.

[001 1 1 ] In the Figure 3 embodiment, coils 53 and 54 are all bifilar.

[001 12] Coils 54 are connected in parallel to an output 55 via a rectification circuit including sub-circuits 56 for each coil 54. It will be noted that sub-circuits 56 are bidirectional to allow for generator 51 to be configured to operate as an electrical motor. A smoothing capacitor is connected across the output terminals defining output 55 to providing smoothing of the rectified voltage that is provided collectively by coils 54 as the rotor and stator rotate relative to each other.

[001 13] Generator 51 includes a starter circuit 57 for inducing rotational movement between the stator and the rotor, which is used to start the rotation if the external source of rotation for generator 51 is not able to provide sufficient toque to overcome any static friction and magnetic forces within generator 51. In this embodiment, circuit 57 includes a single starter coil 58 that is disposed intermediate two of coils 53 and which is selectively energised by switching coil 58 (by way of operating switch 59) in series with an energy source such as a battery 60, to induce the required rotation between the rotor and the stator. In other embodiment different starter circuits are used. For example, in those embodiments where coils 54 (and coils 53) are independently switched, these are able to be selectively energised to perform the operation of circuit 57. [00114] In further embodiments, a plurality of like generators 51 is conjoined along a common axle. That is, the generators are axiaily spaced apart with the stators being fixed with respect to each other, and the rotors rotating in unison within respective stators. In some embodiments, the stators are formed from a single stator member to which the separate wiring circuits are mounted in an axiaily spaced apart configuration. In other embodiments, the stator is formed from a plurality of parallel aluminium plates having substantially central aligned apertures through which the axle extends and between which, in use, the rotors are mounted.

[001 15] A further embodiment of the invention is illustrated in Figure 4, where corresponding features are denoted by corresponding reference numerals. In this embodiment, a generator 61 includes a controller, in the form or a microprocessor based controller 62, that is programmed to operate switch 59 and a further switch 63 to further refine the operation of the generator. In this embodiment, switches 59 and 63 are implemented as high voltage solid state switches via switching unit such as that manufactured and sold under the BEHLKE trademark as model number HTS 71-02 -C. In other embodiments use is made of different switches.

[00116] In other embodiments, outlet 55 acts as an inlet and is connected to a power source such as a rectified mains power network (or another DC power source such as a battery or bank of batteries) and controller 62 operates switch 63 to selectively energise coils 54 and thereby induce rotation between the stator and rotor, it will be appreciated that the voltage applied to the output in this mode of operation will be of an opposite polarity to that shown in the figure.

[00117] Reference is now made to Figures 5 and 6 where corresponding features are denoted by corresponding reference numerals. In particular, there is illustrated a further embodiment of the invention in the form of a generator 71 which includes the stator and wiring of Figure 3. For clarity, circuit 57 has been omitted.

[00118] Generator 71 includes a stator 71a and a rotor 71b mounted to an axle 71c for allowing relative rotation between the stator and rotor. Stator 71 a has an aluminium foot plate 72 from which upwardly extend two parallel and spaced apart generally square aluminium support plates 73 and 74. The support plates are formed from 8 mm thick machined aluminium and are bolted or otherwise secured to plate 72. Plates 73 and 74 are further retained in a fixed parallel configuration by eight equally circumferentially spaced apart axiaily extending aluminium spacers 75. In this embodiment the spacers are formed from 30 mm aluminium round bar and are about 130 mm long axiaily. The opposed faces of plates 73 and 74 include machined radial channels 76, where opposed pairs of those channels slideably receive respective coil assemblies 77.

[001 19] Each coil assembly includes both a respective coil 53 and 54 (not shown in Figures 5 and 6) co-wound about a common former. Those coils 53 and 54 are wired as illustrated in Figure 3. Once received within respective pairs of channels, each assembly 77 is aligned to have their respective radial inner ends as close as possible to the radial periphery of rotor 71b. The intention is to minimise the air gap between the two while preventing direct physical contact. Accordingly, regard is had to the tolerances of the machining that has occurred, the anticipated wear over a given service interval, and a safety margin. Once positioned, each assembly 77 is locked radially by a respective grub screw and then coils 53 and 54 are wired together with the other assemblies to form the required overall electrical circuit.

[00120] Once of assemblies 77 is illustrated in Figure 7. In particular, assembly 77 includes coils 53 and 54 would together to form a composite winding 81 that is wound on a former 82. The former is supported by spaced apart radial inner and radial outer lateral members 83 and 84. The lateral ends of both members 83 and 84 include like engagement channels (not shown) for receiving one of radially extending and laterally spaced apart guide members 85 and 86. These members 85 and 86 are fixedly located with respect to each other by an adjoining bar 87. An adjustment mechanism, in the form of two spaced apart lock bolts 89 and 90 that extend between former 82 and bar 87, allow for selective axial movement of winding 81. That is, as bolts 89 and 90 are rotated, winding 81 moves axiaily as members 83 and 84 are guided by both members 85 and 86.

[00121] in use, members 85 and 86 are received within respective ones of the opposed channels in a pair of channels in plates 73 and 74. Once assembly 77 is radially located, and fixed to one or both of plates 73 and 74, a technician is able to adjust bolts 89 and 90 to fine tune any radial positioning of winding 81. This form of assembly 77 also facilitates any later servicing of generator 71 which requires the radial adjustment of winding 81.

[00122] it will be appreciated that plate 72 is able to be easily extended to also provide a mounting formation for further like support plates such that compound electrical machine formed from adjacent axiaily spaced machines is formed. That is, the components described above enable a substantially modular approach to building an electrical machine. For a twin rotor machine it is possible to use only three suitably formed plates. That is, for an n rotor machine there is a need for only (n + 1) plates). However, in other embodiments, where n > 2, it is possible to have the two end rotors - that is, those rotors between which the other rotor or rotors are disposed - supported on axle 71c and being adjacent only one respective plate. That is, for the n rotors there would be (n - 1) plates.

[00123] In further embodiments, the plates and rotor are disposed either wholly or partly within a housing or other enclosure. [00124] Accordingly, the above embodiment provides an electrical machine, in the form of generator 71, which includes:

a plurality of substantially parallel plates 73 and 74;

an axle 71c extending substantially normal to and being supported by one or more of the plates 73 and 74;

a rotor 71b that is mounted to the axle 71c for rotation relative to the plates 73 and 74, where the rotor includes a circumferential periphery at or adjacent to which are disposed a plurality of spaced apart permanent magnets 52 that generate respective magnetic fields; and

a plurality of coil assemblies 77 being supported by one or more or the plates (73, 74) and past which the magnetic fields are selectively moved to transfer energy between the rotor 71b and the assemblies 77.

[00125] For generator 71 , the transfer of energy is from rotational energy of rotor 71 b to electrical energy generated by the coils in assemblies 77. If the electrical machine is operated as an electric motor, the transfer of electrical energy supplied to the coils in assemblies 77 to rotational energy of rotor 71b.

[00128] It is postulated by the inventor that the arrangements of the above embodiments are aided in their operation by tapping energy from the quantum, foam that formed from charged particles that are resident in the atmosphere caused by the solar rays of the sun. This produces a localised vacuum at a point in space at a moment of time from the pulsing a magnetic field created with an electrical current. The surrounding aetheric pressure rushes in to fill the vacuum space and there are resident in that space charged particles that influence the operation of the embodiments. This method of energy conversion is discussed in US patent 7,379,286 (Haisch et. al), the disclosure of which is incorporated herein in its entirety.

[00127] The major advantages of the different preferred embodiments of the invention include:

* Greater energy efficiency relative to existing generators, motors and other electrical machines.

* improved operational flexibility.

® Reduced size and weight for a given output.

» Lower life -cycle costs.

* Simple, low loss construction.

« Uses rare-earth permanent magnets on the rotor. No coils are used on the rotor. * As use is made of permanent magnets on the rotor, there is no need to input energy to the rotor coils.

* No brushes are required as there is no longer a need for an electrical link between the rotor and the stator. This reduces losses.

® Less copper is required in the stator coils.

* Reliance is placed upon the properties of the magnets to create the required forces, rather than a large number of windings carrying high levels of current. Accordingly, resistance losses are reduced.

* A wide range of operating temperatures.

* Generates less heat, and is less susceptible to temperature variation and thermal runaway effects.

* Relatively inexpensive to manufacture.

* By using amorphous polycrystalline ferrite compound, expensive components made from Metgiass or specially laminated steels are able to be eliminated from the machine. That is, it becomes possible for the entire structure of the machine to be made of extruded components of plastic/ferrite.

* Lower 12R losses.

* The elimination of hard iron cores in the stator. This removes from the machine a source of heat (generated in conventional machines due to induction).

* Using one or more amorphous metals in the rotor reduces the hysteresis losses which are normally found in iron, as well as the inductive heat build up.

* Using amorphous metal, in the rotor provides magnetic energy densities up to ten times higher than those of conventional materials, which allows for a more compact and efficient design.

* Accommodates a variety of design configurations, including those requiring high power outputs and/or low starting torque.

[00128] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description. [00129] Similarly, it is to be noticed that the term connected, when used in the claims, should not be interpreted as being limited to direct connections or couplings only. The terms "coupled" and "connected," along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. Thus, the scope of the expression a device A coupled to a device B should not be limited to devices or systems wherein an output of device A is directly connected to an input of device B. It means that there exists a path between an output of A and an input of B which may be a path including other devices or means. "Coupled" or "connected" may mean that two or more elements are either in direct physical or electrical contact, or that two or more elements are not in direct contact with each other but yet still co-operate or interact with each other.

[00130] Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as falling within the scope of the invention. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks.

Claims

1. A brushless electrical machine including:

a rotor having:

a rotor core with a periphery; and

relative rotation between the stator and the rotor; and

a voltage across the second coils.

2. A brushless electrical machine according to claim 1 wherein the plurality of permanent magnets present the same polarity at the periphery.

3. A brushless electrical machine according to claim 1 wherein the plurality of permanent magnets present alternate polarities at the periphery.

4. A brushless electrical machine according to any one of the preceding claims wherein the plurality of permanent magnets includes a number of magnets that is even.

5. A brushless electrical machine according to any one of the preceding claims wherein the number of magnets is an integral multiple of four.

8. A brushless electrical machine according to any one of the preceding claims wherein the magnets in the plurality of permanent magnets are equally angularly spaced about the periphery.

7. A brushless electrical machine according to any one of the preceding claims wherein the first coils are each wound around respective cores.

8. A brushless electrical machine according to claim ? wherein the second coils are each wound around respective cores shared with a corresponding first coil.

9. A brushless electrical machine according to any one of the preceding claims wherein the first coils include first windings of a common first diameter and the second coils include second windings of a common second diameter.

10. A brushless electrical machine according to claim 9 wherein the common first diameter is about 0.50 to 0.60 mm.

1 1. A brushless elecirical machine according to claim 9 or claim 10 wherein the common first diameter is about 0.55 mm.

12. A brushless electrical machine according to any one of claims 9 to l l wherein the common second diameter is about 0.40 to 0.50 mm.

13. A brushless electrical machine according to any one of claims 9 to 12 wherein the common second diameter is about 0.46 mm.

14. A brushless electrical machine according to claim 9 wherein the common first diameter is greater than the common second diameter.

15. A brushless electrical machine according to claim 9 wherein the common first diameter is about 18% to 21% greater than the common second diameter.

18. A brushless electrical machine according to any one of the preceding claims wherein the second coils are connected in parallel to an output.

17. A brushless electrical machine according to claim 16 wherein the second coils are connected to the output via a rectification circuit.

18. A brushless electrical machine according to claim 17 wherein the rectification circuit is bidirectional.

19. A brushless electrical machine according to any one of the preceding claims wherein:

the stator includes a plurality of substantially parallel plates;

an axle extends substantially normal to is supported by one or more of the plates; the rotor is mounted to the axle for rotation relative to the plates and the permanent magnets generate respective magnetic fields;

a plurality of coil assemblies including respective pairs of the first and second coils is supported by one or more of the plates; and

the magnetic fields are selectively moved past the assemblies to transfer energy between the rotor and the assemblies.

20. A brushless electrical machine according to claim 19 the plates, in use, include opposed faces having respective radially extending mounting formations for releasably slideably receiving the coil assemblies.