Rotating mass energy store

Abstract

A rotating mass energy store includes a rotor (10) that contains conductors (6), (7), (18), (17) and magnet arrangement (11). The rotating mass is symmetrical about the axis of rotation and is hollow with a cavity (24), wherein an electrical stator (12) is located in the cavity. All components of the energy store are enclosed in a housing (1) which has a fitting / connection (2) for a vacuum pump and / or seal, and wire connection seals (3) and (15) for conductive wires to pass through. The rotor (10) is permanently magnetically levitated axially and radially. Electrical energy is exchanged and stored as kinetic energy in a rotating mass, otherwise known as the rotor (10).

Description

TITLE: ROTATING MASS ENERGY STORE DESCRIPTION FIELD OF THE INVENTION This invention relates to a rotating mass energy store. BACKGROUND ART Energy is required to be stored so that it can be used at a later time than when it was once generated. Energy can be stored in different ways. An energy store that uses chemicals to store potential energy is harmful to the environment when it is disposed or recycled. SUMMARY OF THE INVENTION To overcome this problem, this present invention proposes kinetic energy storage without using chemicals or dangerous materials. This invention stores energy kinetically by means of a rotating mass, also known as a rotor. This invention eliminates some components that are in existing rotary energy store designs, which reduces material usage and increases energy and power density. Natural properties of materials are utilised to form a more effective and efficient energy store that does not harm the environment. WSLEGAL\057309\00039\36209508v1 In accordance with the present invention there is provided a rotary energy store comprising a permanently magnetically levitated rotor. In one embodiment, the permanently magnetically levitated rotor is part of an integrated motor-generator unit. In one embodiment, the permanent magnetic levitation system comprises radial permanent magnetic bearings. In one embodiment, the permanent magnetic levitation system comprises axial permanent magnetic bearings. In one embodiment, the radial permanent magnetic bearings are electrodynamic bearings. In one embodiment, the axial permanent magnetic bearings use Halbach array magnet arrangements to produce levitation forces. In one embodiment, the rotor is in a sealed housing. The sealed housing may have a connected vacuum pump to form a vacuum environment for the rotor to rotate in. In one embodiment, the housing secures one or more of (e.g. two or more of or all of): the stator of the motor-generator unit; the magnets of the radial electrodynamic bearings; and the axial permanent magnetic bearings. In one embodiment, the stator is located equidistant between first and second axial permanent magnetic bearings. In one embodiment, the rotor is a hollow body (e.g. hollow symmetrical body). In one embodiment, the hollow body contains embedded magnets in its wall that form part of the motor-generator unit. In one embodiment, the hollow body contains embedded conductors that form part of complete radial electrodynamic bearings and / or part of complete axial permanent magnetic bearings. In one embodiment, the magnets embedded in the rotor rotate about the stator and are also equidistant between both axial permanent magnetic bearings. In one embodiment, the conductors for the radial electrodynamic bearings are located such that the conductors are aligned with the radial bearing magnets (e.g. so the conductor within the wall rotates about the radial bearing magnets secured by the housing). In one embodiment, the conductors for the axial permanent magnetic bearings are located such that the conductor is embedded in the rotor at the rotor's open end, so the sequence of arrangement is: rotor with embedded conductor, a gap, and the axial permanent magnet arrangement which is secured in place by the housing. This sequence may change direction but remains in the same order as the arrangement will be at both ends of the rotor. In one embodiment, the rotary energy store of the present invention has a rotor that is 5 magnetically levitated axially and radially. The rotor may have a hollow structure that is symmetric axially and radially, it has the majority of its mass at its circumference and contains magnets and conductors within its wall. In one embodiment, these magnets in the rotor wall are part of an integrated motor- generator unit where the rotor is forced to rotate about an electrical stator owing to induction. The magnets within the wall of the rotor may have a polarisation sequence that forms a Halbach array producing an augmented magnetic field in the inner cavity of the rotor where the stator is located. An integrated motor-generator unit means that the motor-generator is not a separate part from the rotor, the rotor is used to be part of the motor-generator unit. In one embodiment, the rotor is made of a composite material. In one embodiment, the electrical stator is static. The stator may have multiple poles, which are extended parts of the geometry and are equally spaced radially. Each pole may hold a coil winding. A coil winding is where electrically conductive wire is wrapped around the bulk of the pole multiple times. Each coil winding has 'tails' that are where the coil begins and where the coil ends. When electrical current is conducted by the conductive wire of the coil windings, by induction, the rotor is forced to rotate about the stator. Depending on the direction of the current, the rotor will be forced to rotate faster relative to prior motion or rotate slower relative to prior motion. When electrical current is drawn from the coil winding wire, leaving the energy store, the rotor will slow down. When electrical current is applied to the wire, going into the energy store, the rotor will rotate faster. In one embodiment, the stator is made of iron. In one embodiment, the electrically conductive wire is made of copper. In one embodiment, a housing structure encloses all moving parts of the energy store. The housing may possess a fitting that is able to connect a vacuum pump and or vacuum system and or vacuum seal so that a vacuum or low pressure environment can be created within the housing cavity. The housing may secure the location of the magnets and iron pole shoes of the radial electrodynamic bearings and the magnets of the axial permanent magnetic bearings, this may be by means of brackets or similar fixing preferably made from a non-conducting material. In one embodiment, the coil winding tails extend to the housing and through a seal so 5 that electrical current can be exchanged to and from the energy store, but without air leakage. In one embodiment, the axial and radial levitation magnetic bearings are both permanent magnetic bearings. In one embodiment, the radial magnetic bearings prevent gyration about the axis of rotation and contact between stationary and moving parts of the energy store. In one embodiment, the radial magnetic bearings are electrodynamic bearings, comprising a hollow cylindrical stack of alternating iron rings and ring magnets, the stack sequence begins and ends with iron rings, these may be known as iron pole shoes. The iron pole shoes and ring magnets may have the geometry of a shallow hollow cylinder. In one embodiment, a conductor is embedded in the wall of the rotor aligned with the location of the electrodynamic bearings, which gives rise to repulsive forces between the conductor itself and the electrodynamic bearing, levitating and stabilising the rotor. As the electrodynamic bearings are located near the ends of the rotor, the conductor for the electrodynamic bearing will be located in the wall of the rotor so that it aligns with the electrodynamic bearings. Each electrodynamic bearing may have at least one conductor that is embedded in the wall of the rotor. In one embodiment, axial magnetic bearings prevent touchdown of the rotor. Touchdown is where levitation is lost and the rotor falls (possibly whilst rotating) and hits a static part of the energy store. In one embodiment, the axial magnetic bearings are arrangements of permanently polarised magnet segments that form a ring shape. The sequence of polarised magnets may be in the form of a Halbach array where the augmented field is where the rotor is located, wherein a conductor is embedded in the rotor wall. Repulsive forces arise between the conductor embedded in the rotor wall and the arrangement of polarised magnets. As the axial magnetic bearings are located at the extremities of the rotor length, the conductor in the rotor wall will be located close to the rotor end(s). The conductor can be in the form of a torus, or coil, or a combination of both, the conductor can be made from more than one piece. WSLEGAL\057309\00039\36209508v1 Date received 2024-05-31 A Halbach array is a sequence of magnets with a particular polarisation pattern. The sequence is of magnets that are alternatively polarised laterally and longitudinally. However, the longitudinally polarised magnets alternatively change polarity. The laterally polarised magnets also alternatively change polarity. So the base sequence is four magnets long, and this sequence repeats. This sequence can be formed into a geometrical shape but the relative sequence / pattern remains. BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the present invention will now be described solely by way of example and reference to the accompanying drawings in which: Figures 1, 2, 3A-C, 4A-B and 5A-C show component parts of a rotary energy store in accordance with an embodiment of the present invention; and Figure 6 shows the rotary energy store in accordance with the embodiment of the 15 present invention. DETAILED DESCRIPTION Figure 1 shows a Halbach array sequence where N5 is the augmented magnetic field, N2 and N4 are the longitudinally polarised magnets, alternating in direction, N3 and N1 are the laterally polarised magnets, alternating in direction. The magnets are equal in size. Figure 2 shows the cross section of the electrodynamic bearing that provides radial stability and levitation. The interacting conductor and securing shaft / bracket is also shown, as if it was cut in half down its centre. The electrodynamic bearing comprises iron pole shoes 19 that are ring shaped, ring magnets 20, a securing shaft 22 that is attached to or part of the housing, a conductor 18 embedded in the rotor wall 10A of the rotor. Figures 3A-3B show the axial permanent magnetic bearing with its interacting conductor and securing method. In Figure 3A a cross section of the axial permanent magnetic bearing and the securing method is shown, where 16 is a magnet ring, 1 is the housing which partially encloses the axial permanent magnetic bearing which comprises magnet segments, 22 the shaft attached to or part of the housing 1 which leads to securing other components, 17 is the torus conductor, which can be solid or coil shaped and 10A the rotor wall. As illustrated, the housing 1 is of a geometry that partially encloses the magnet ring 16 of the axial permanent magnetic bearing, shaft 22 can be part of the housing 1. The torus conductor 17 is embedded in the rotor wall 10A. The rotor 10 including the embedded torus conductor 17 levitate about the magnet ring 16 of the axial permanent magnetic bearing which is secured in place by housing 1. Figure 3B shows the top view of the magnet ring 16 of the axial permanent magnetic bearing of Figure 3A. The segments that form the 'ring' are shown with their polarisation directions. Every alternative magnet is polarised tangentially, and each other magnet is polarised either into or out of the paper, labelled as M2 and M1 respectively. The tangentially polarised magnets M3 alternate in the tangential direction. The magnets with polarisation direction into the paper are labelled M2. The magnets with polarisation direction out of the paper are labelled M1. Figure 3C shows the top view of the torus conductor 17. Figure 4A represents rotor 10 with its embedded magnets and conductors. Torus conductors 6, 17 and radial conductors 7, 18 are embedded in the rotor wall 10A, rotor magnets 11 are embedded in the wall 10A of the rotor near the inner surface of the rotor cavity 24 where the electrical stator would be located. Figure 4B shows the top view of the rotor magnets and their polarisation direction. The polarisation pattern comprises tangentially polarised magnets and radially polarised magnets. The pattern alternates between tangentially and radially polarised magnets, and these alternate too. M1 and M2 are both radially polarised, but are in opposing directions, where M1 is polarised towards the circumference of the ring, and M2 is polarised towards the centre of the ring. M3 and M4 are both tangentially polarised magnets, but are polarised in opposite directions. The base sequence comprises of M1, M2, M3 and M4 which repeats to form the pattern. The polarisation pattern of magnets creates an augmented magnetic field on the inside of the ring, labelled M5. Figure 5A shows the top view of the electrical stator 12 comprising pole head 12A, electrically conductive wire 12B, pole piece 12C, and stator core 12D. The stator 12 has more than one pole, usually five or six. The poles are equally spaced around the stator core 12D. Each pole piece 12C has a pole head 12A, the conductive wire 12B is wrapped around the pole piece 12C for at least one complete turn, but can have multiple turns. Figure 5B shows how the conductive wire 12B of Figure 5A is wrapped around the pole piece 12C of Figure 5A. In Figure 5B, 12A is the pole head, 12C is the pole piece, and 12E and 12F show the coil 'tails'. The coil tails 12E and 12F are extensions of the conductive wire 12B that extend from where the coil starts and where the coil ends, in other words, where the coil leads to the coil and leaves the pole piece 12C. Figure 5C shows the pole piece 12C of Figure 5A and how the conductive wire 12B of Figure 5A wraps around it. In Figure 5C, 12A is the pole head, 12C is the pole piece and 12E and 12F are the coil 'tails'. The conductive wire 12B wraps around the pole piece 12C for two whole turns and leaves the pole piece 12C with the coil tail extension 12F. Figure 6 shows the rotary energy store with the majority of its components. Housing 1 can have a fitting or connection 2 that can connect with a vacuum pump and or seal that is able to create a vacuum environment within the cavity 14 of the housing 1. The housing 1 also has at least one seal that holds a wire through the housing and does not allow air leakage to occur to or from the energy store. The drawing shows the housing with two wire seals 3 and 15. The housing 1 has a cavity 14 where most of the components go, and where the vacuum environment is created. The housing 1 has a shaft 22 that is through its centre, with a channel 4, and at either end of the shaft are two wire seals 3 and 15. The shaft 22 has additional small channels 13 and 21 that allow the coil tails 12E and 12F of Figure 5B to go from the poles of the stator 12 through to the centre channel 4 of the shaft 22 and to the wire seals 3 and 15, that then leave the energy store for energy exchange. The shaft 22 secures the stator 12 in place. The stator 12 is located on the shaft 22 in the housing 1 so that it is equidistant from either axial magnetic bearing. The geometry of housing 1 secures the location of the magnet rings 5 and 16 of the axial permanent magnet bearing. The rotor 10 is levitated within the housing cavity 14 about the shaft 22, between the magnet rings 5 and 16 of the axial permanent magnetic bearing and about the multiple iron pole shoes 8 and 19 and multiple ring magnets 9 and 20 of the electrodynamic bearings, which are stacked alternatively, and explained in Figure 2. The iron pole shoes 8 and 19 and multiple ring magnets 9 and 20 of the electrodynamic bearings are secured in place on the shaft 22. The rotor 10 has components embedded in its wall. The rotor 10 has 'open' ends so that it can rotate about the electrodynamic bearing that is secured by a shaft. Two torus 5 conductors 6 and 17 are embedded in the rotor wall at the extremities of the rotor 10. Two conductors 7 and 18 are embedded in the rotor wall for each radial electrodynamic bearing, and are embedded so that they are aligned with the electrodynamic bearing. The rotor 10 also has magnets 11 embedded in its main bulk near the inner surface 23 of the rotor cavity 24. The rotor magnets 11 are located such that they are aligned with the stator 12 for interaction 10 to occur.

Claims

1. A rotary energy store comprising: a housing defining a cavity; a motor-generator unit provided within the cavity, the motor-generator unit including a stator secured to the housing and a permanently magnetically levitated rotor; wherein the rotor comprises a rotor body containing at least one embedded conductor forming, in combination with magnets secured to the housing, a complete axial permanent magnetic bearing of a permanent magnetic levitation system; 10 wherein the at least one embedded conductor is a torus conductor coil.

2. A rotary energy store according to claim 1 where the rotor body further contains at least one embedded conductor forming, in combination with the magnets secured to the housing, a complete radial permanent magnetic bearing of the permanent magnetic levitation 15 system.

3. A rotary energy store according to claim 1 where the rotor body is a hollow body.

4. A rotary energy store according to claim 2 where the complete radial permanent 20 magnetic bearing is a radial electrodynamic bearing and the complete axial permanent magnetic bearing uses a Halbach array magnet arrangement to produce levitation forces.

5. A rotary energy store according to claim 1 where the rotor is in a sealed housing that has a connected vacuum pump to form a vacuum environment in the cavity of the housing for the rotor to rotate in.

6. A rotary energy store according to claim 1 where the complete axial permanent magnetic bearing comprises first and second axial permanent magnetic bearings and the stator is located equidistant between the first and second axial permanent magnetic bearings.

7. A rotary energy store according to claim 6 where the rotor body further contains embedded magnets in a wall of the rotor body.

8. A rotary energy store according to claim 7 where the embedded magnets within the wall of the rotor have a polarisation sequence that forms a Halbach array producing an augmented magnetic field. 5 9. A rotary energy store according to claim 8 where the Halbach array produces the augmented magnetic field in an inner cavity of the rotor where the stator is located.

10. A rotary energy store according to claim 7 where the embedded magnets within the rotor rotate about the stator and are also equidistant between the first and second axial permanent magnetic bearings.

11. A rotary energy store according to claim 4 where the at least one embedded conductor of the radial electrodynamic bearing is located such that the at least one embedded conductor is aligned with radial bearing magnets of the radial permanent magnetic bearing, so the at least one embedded conductor within the rotor rotates about the radial bearing magnets secured by the housing.

12. A rotary energy store according to claim 1 where the at least one embedded conductor of the complete axial permanent magnetic bearing is located such that the at least one embedded conductor is embedded in the rotor at an open end of the rotor, so the sequence of arrangement is: the rotor, a gap, and the complete axial permanent magnet bearing which is secured in place by the housing.