NOVEL DOUBLE-STATOR COMBINED ELECTRIC MACHINE SUITABLE FOR ACHIEVING SENSORLESS CONTROL OF ABSOLUTE POSITION OF ROTOR

Abstract

A double-stator and electric machine suitable for achieving sensorless control of the absolute position of a rotor. An inner stator is fixed to a stationary shaft, an outer stator and the inner stator are concentric, and the above components form a stationary part of the electric machine. A rotor is assembled between the outer stator and the inner stator, and forms a rotating part of the electric machine with a moving shaft through a front rotor support. The rotating part is isolated from a front end cap through a front outer bearing. The rotating part is isolated from a back end cap through a back outer bearing after the rotating part is connected with a back rotor support. The moving shaft is isolated from the stationary shaft through an inner bearing.

Claims

1-8. (canceled)

9. A double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor, wherein an outer stator and the outer side of a rotor form an outer air-gap electric machine, and an inner stator and the inner side of the rotor form an inner air-gap electric machine; the type of the outer air-gap electric machine and the type of the inner air-gap electric machine may be formed by combining two types of the following electric machines or one type of the following electric machines in pairs: a permanent magnet synchronous machine, a synchronous reluctance machine, a switched reluctance machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine and the like; or the type of the outer air-gap electric machine and the type of the inner air-gap electric machine may be formed by combining one type of the above electric machines with a reluctance or wound type rotary transformer.

10. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 9, wherein the numbers of pole pairs p1 and p2 of two air-gap electric machines meet the following basic rule: (1), p1≠p2, the greatest common divisors of the p1 and the p2 are equal to 1, and the p1 and the p2 are positive integers; or (2), |m.Math.p1−n.Math.p2|=1, the p1 and the p2 are positive integers, and the m and the n are positive integers.

11. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 10, wherein the numbers of pole pairs p1 and p2 of two air-gap electric machines meet the following basic rule: p1=p2+1 or p1=p2−1, the p1 and the p2 are positive integers.

12. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 10, wherein the numbers of pole pairs p1 and p2 of two air-gap electric machines meet the following basic rule: p1=2, the p2 is any positive odd number or equal to 2, and the p1 is any positive odd number.

13. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 10, wherein the numbers of pole pairs p1 and p2 of two air-gap electric machines meet the following basic rule: p1=1, the p2 is any positive integer or equal to 1, and the p1 is any positive integer.

14. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 9, wherein the type of the electric machine is a synchronous machine, comprising a permanent magnet synchronous machine, a brushless permanent magnet machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine, a synchronous reluctance machine, a switched reluctance machine, and a reluctance or wound type rotary transformer.

15. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 10, wherein the type of the electric machine is a synchronous machine, comprising a permanent magnet synchronous machine, a brushless permanent magnet machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine, a synchronous reluctance machine, a switched reluctance machine, and a reluctance or wound type rotary transformer.

16. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 11, wherein the type of the electric machine is a synchronous machine, comprising a permanent magnet synchronous machine, a brushless permanent magnet machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine, a synchronous reluctance machine, a switched reluctance machine, and a reluctance or wound type rotary transformer.

17. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 12, wherein the type of the electric machine is a synchronous machine, comprising a permanent magnet synchronous machine, a brushless permanent magnet machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine, a synchronous reluctance machine, a switched reluctance machine, and a reluctance or wound type rotary transformer.

18. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 13, wherein the type of the electric machine is a synchronous machine, comprising a permanent magnet synchronous machine, a brushless permanent magnet machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine, a synchronous reluctance machine, a switched reluctance machine, and a reluctance or wound type rotary transformer.

19. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 9, wherein the electric machine topology has a double-stator structure of a radial-magnetic-field electric machine, the direction of magnetic field of the air gap is radial, and the motion manner is rotation; the electric machine topology can be applied to a double-stator and multiple-stator structure of an axial-magnetic-field electric machine, the direction of magnetic field of the air gap is axial, the stators and the rotor are disc-shaped, and the motion manner is rotation; the electric machine topology can be applied to a double-stator single-rotor linear electric machine structure and a planar electric machine structure.

20. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 10, wherein the electric machine topology has a double-stator structure of a radial-magnetic-field electric machine, the direction of magnetic field of the air gap is radial, and the motion manner is rotation; the electric machine topology can be applied to a double-stator and multiple-stator structure of an axial-magnetic-field electric machine, the direction of magnetic field of the air gap is axial, the stators and the rotor are disc-shaped, and the motion manner is rotation; the electric machine topology can be applied to a double-stator single-rotor linear electric machine structure and a planar electric machine structure.

21. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 11, wherein the electric machine topology has a double-stator structure of a radial-magnetic-field electric machine, the direction of magnetic field of the air gap is radial, and the motion manner is rotation; the electric machine topology can be applied to a double-stator and multiple-stator structure of an axial-magnetic-field electric machine, the direction of magnetic field of the air gap is axial, the stators and the rotor are disc-shaped, and the motion manner is rotation; the electric machine topology can be applied to a double-stator single-rotor linear electric machine structure and a planar electric machine structure.

22. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 12, wherein the electric machine topology has a double-stator structure of a radial-magnetic-field electric machine, the direction of magnetic field of the air gap is radial, and the motion manner is rotation; the electric machine topology can be applied to a double-stator and multiple-stator structure of an axial-magnetic-field electric machine, the direction of magnetic field of the air gap is axial, the stators and the rotor are disc-shaped, and the motion manner is rotation; the electric machine topology can be applied to a double-stator single-rotor linear electric machine structure and a planar electric machine structure.

23. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 13, wherein the electric machine topology has a double-stator structure of a radial-magnetic-field electric machine, the direction of magnetic field of the air gap is radial, and the motion manner is rotation; the electric machine topology can be applied to a double-stator and multiple-stator structure of an axial-magnetic-field electric machine, the direction of magnetic field of the air gap is axial, the stators and the rotor are disc-shaped, and the motion manner is rotation; the electric machine topology can be applied to a double-stator single-rotor linear electric machine structure and a planar electric machine structure.

24. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 19, wherein the arrangement manner of permanent magnets can be radial arrangement, tangential arrangement and combined arrangement; the combined arrangement comprises U-shaped arrangement, V-shaped arrangement, W-shaped arrangement, the other radial-tangential combined arrangement, and variations of the other electric machine structures.

25. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 20, wherein the arrangement manner of permanent magnets can be radial arrangement, tangential arrangement and combined arrangement; the combined arrangement comprises U-shaped arrangement, V-shaped arrangement, W-shaped arrangement, the other radial-tangential combined arrangement, and variations of the other electric machine structures.

26. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 21, wherein the arrangement manner of permanent magnets can be radial arrangement, tangential arrangement and combined arrangement; the combined arrangement comprises U-shaped arrangement, V-shaped arrangement, W-shaped arrangement, the other radial-tangential combined arrangement, and variations of the other electric machine structures.

27. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 22, wherein the arrangement manner of permanent magnets can be radial arrangement, tangential arrangement and combined arrangement; the combined arrangement comprises U-shaped arrangement, V-shaped arrangement, W-shaped arrangement, the other radial-tangential combined arrangement, and variations of the other electric machine structures.

28. The double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor according to claim 23, wherein the arrangement manner of permanent magnets can be radial arrangement, tangential arrangement and combined arrangement; the combined arrangement comprises U-shaped arrangement, V-shaped arrangement, W-shaped arrangement, the other radial-tangential combined arrangement, and variations of the other electric machine structures.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a radial sectional view of a radial-magnetic-field double-stator combined electric machine of the present invention.

[0019] FIG. 2 is a radial cross sectional view of a double-stator combined electric machine combining two permanent magnet synchronous machines in the present invention.

[0020] FIG. 3 is a radial cross sectional view of a double-stator combined electric machine combining a permanent magnet synchronous machine and a synchronous reluctance machine in the present invention.

[0021] FIG. 4 is a radial cross sectional view of a double-stator combined electric machine combining a synchronous reluctance machine and a permanent magnet synchronous machine in the present invention.

[0022] FIG. 5 is a radial cross sectional view of a double-stator combined electric machine combining two synchronous reluctance machines in the present invention.

[0023] FIG. 6 is an axial cross sectional view of a double-stator combined disc-type electric machine combining two permanent magnet synchronous machines in the present invention.

[0024] FIG. 7 is a cross sectional view of a double-stator combined linear electric machine combining two permanent magnet synchronous machines in the present invention.

[0025] In the drawings: 1—moving shaft, 2—front end cap, 3—front outer bearing, 4—front rotor support, 5—inner stator, 6—rotor, 7—outer stator, 8—housing, 9—stationary shaft, 10—back rotor support, 11—back outer bearing, 12—retainer ring, 13—inner bearing, 14—back end cap, 15—small back end cap, 16—inner stator winding, 17—outer stator winding, 18—inner air gap permanent magnet, and 19—outer air gap permanent magnet.

DESCRIPTION OF THE EMBODIMENTS

[0026] The present invention is further described below with reference to the accompanying drawings through embodiments.

Embodiment 1

[0027] A novel double-stator combined electric machine suitable for achieving sensorless control of the absolute position of a rotor of the present invention is achieved by the following solution:

[0028] As shown in FIG. 1, an electric machine housing 8 sleeves an outer stator 7. The outer stator is limited by a retainer ring 12 and then is tightly clamped by a front end cap 2 and a back end cap 14. A stationary shaft 9 and a small back end cap 15 are mounted at the center of the back end cap 14. An inner stator 5 is fixed to the stationary shaft 9, the outer stator 7 and the inner stator 5 are concentric, and the above components form a stationary part of the electric machine. A rotor 6 is assembled between the outer stator 7 and the inner stator 5, and forms a rotating part of the electric machine with a moving shaft 1 through a front rotor support 4. The rotating part is isolated from the front end cap 2 through a front outer bearing 3. The rotating part is isolated from the back end cap 14 through a back outer bearing 11 after the rotating part is connected with a back rotor support 10. The moving shaft 1 is isolated from the stationary shaft 9 through an inner bearing 13.

[0029] The outer stator 7 and the outer side of the rotor 6 form an outer air-gap electric machine, and the inner stator 5 and the inner side of the rotor 6 form an inner air-gap electric machine. The type of the outer air-gap electric machine and the type of the inner air-gap electric machine may be formed by combining two types of the following electric machines or one type of the following electric machines in pairs: a permanent magnet synchronous machine (a brushless permanent magnet machine), a synchronous reluctance machine, a switched reluctance machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine and the like; or the type of the outer air-gap electric machine and the type of the inner air-gap electric machine may be formed by combining one type of the above electric machines with a reluctance or wound type rotary transformer. Specifically,

[0030] (1), the two permanent magnet synchronous machines (brushless permanent magnet machines) are combined;

[0031] (2), the permanent magnet synchronous machine (the brushless permanent magnet machine) and the synchronous reluctance machine are combined;

[0032] (3), the permanent magnet synchronous machine (the brushless permanent magnet machine) and the switched reluctance machine are combined;

[0033] (4), the permanent magnet synchronous machine (the brushless permanent magnet machine) and the electrically excited synchronous machine are combined;

[0034] (5), the permanent magnet synchronous machine (the brushless permanent magnet machine) and the hybrid excitation synchronous machine are combined;

[0035] (6), the permanent magnet synchronous machine (the brushless permanent magnet machine) and the reluctance or wound type rotary transformer are combined;

[0036] (7), the two synchronous reluctance machines are combined;

[0037] (8), the synchronous reluctance machine and the switched reluctance machine are combined;

[0038] (9), the synchronous reluctance machine and the electrically excited synchronous machine are combined;

[0039] (10), the synchronous reluctance machine and the hybrid excitation synchronous machine are combined;

[0040] (12), the hybrid excitation synchronous machine and the reluctance or wound type rotary transformer are combined;

[0041] (13), the two switched reluctance machines are combined;

[0042] (14), the switched reluctance machine and the electrically excited synchronous machine are combined;

[0043] (14), the switched reluctance machine and the hybrid excitation synchronous machine are combined;

[0044] (15), the switched reluctance machine and the reluctance or wound type rotary transformer are combined;

[0045] (16), the two electrically excited synchronous machines are combined;

[0046] (17), the electrically excited synchronous machine and the hybrid excitation synchronous machine are combined;

[0047] (18), the electrically excited synchronous machine and the reluctance or wound type rotary transformer are combined;

[0048] (19), the two hybrid excitation synchronous machines are combined;

[0049] (20), the hybrid excitation synchronous machine and the reluctance or wound type rotary transformer are combined.

[0050] The numbers of pole pairs p1 and p2 of the two air-gap electric machines meet the following basic rule:

[0051] (1), p1≠p2, the greatest common divisors of the p1 and the p2 are equal to 1, and the p1 and the p2 are positive integers;

[0052] or,

[0053] (2), |m.Math.p1−n.Math.p2|=1, the p1 and the p2 are positive integers, and the m and the n are positive integers;

[0054] or,

[0055] (3), p1=p2+1 or p1=p2−1, the p1 and the p2 are positive integers;

[0056] or,

[0057] (4), p1=2, the p2 is any positive odd number or equal to 2, and the p1 is any positive odd number;

[0058] or,

[0059] (5), p1=1, the p2 is any positive integer or equal to 1, and the p1 is any positive integer.

[0060] FIG. 2 is a radial cross sectional view of a double-stator combined electric machine combining two permanent magnet synchronous machines. An inner stator winding 16 winds around the inner stator 5. Inner air gap permanent magnets 18 are embedded in the inner side of the rotor 6. An outer stator winding 17 winds around the outer stator 7. Outer air gap permanent magnets 19 are embedded in the outer side of the rotor 6. In FIG. 2, the number of pole pairs of an outer air gap is 3 and the number of pole pairs of an inner air gap is 2.

[0061] FIG. 3 is a radial cross sectional view of a double-stator combined electric machine combining a permanent magnet synchronous machine and a synchronous reluctance machine. The inner stator winding 16 winds around the inner stator 5. The outer stator winding 17 winds around the outer stator 7. The outer air gap permanent magnets 19 are embedded in the outer side of the rotor 6. In FIG. 3, the number of pole pairs of the outer air gap is 3 and the number of pole pairs of the inner air gap is 2.

[0062] FIG. 4 is a radial cross sectional view of a double-stator combined electric machine combining a synchronous reluctance machine and a permanent magnet synchronous machine. The inner stator winding 16 winds around the inner stator 5. The inner air gap permanent magnets 18 are embedded in the inner side of the rotor 6. The outer stator winding 17 winds around the outer stator 7. In FIG. 4, the number of pole pairs of the outer air gap is 3 and the number of pole pairs of the inner air gap is 2.

[0063] FIG. 5 is a radial cross sectional view of a double-stator combined electric machine combining two synchronous reluctance machines. The inner stator winding 16 winds around the inner stator 5. The outer stator winding 17 winds around the outer stator 7. In FIG. 5, the number of pole pairs of the outer air gap is 3 and the number of pole pairs of the inner air gap is 2.

[0064] The type of the electric machine in the embodiment is a synchronous machine. The synchronous machine mainly includes a permanent magnet synchronous machine, a brushless permanent magnet machine, an electrically excited synchronous machine, a hybrid excitation synchronous machine, a synchronous reluctance machine, a switched reluctance machine, and a reluctance or wound type rotary transformer.

[0065] Specific electric machine structures in the embodiment are merely for illustrative purposes. Besides, the moving shaft 1 in FIG. 1 has shaft extensions at the front end cap and the back end cap, or may have only one shaft extension. The stationary shaft 9, the back end cap 14 and the small back end cap 15 are separated or integrated. A cooling water channel may be opened in the housing 8 and the stationary shaft 9, respectively. Or, according to the actual temperature increase situation, the water channel is not opened, but an air cooling manner, a natural cooling manner and the like are utilized. The present invention can also utilize variations of the other electric machine structures.

[0066] An arrangement manner of the permanent magnets shown in the embodiment is merely for illustrative purposes. Besides the radial arrangement shown in FIG. 2, FIG. 3 and FIG. 4, tangential arrangement and combined arrangement can be also utilized. The combined arrangement comprises U-shaped arrangement, V-shaped arrangement, W-shaped arrangement, and the other radial-tangential combined arrangement.

Embodiment 2

[0067] FIG. 6 is an axial cross sectional view of a double-stator combined disc-type electric machine combining two permanent magnet synchronous machines. A left stator winding is wound in a left stator 20. A left air gap permanent magnet 21 is adhered to the left side surface of the rotor 6. A right stator winding is wound in a right stator 23. A right air gap permanent magnet 22 is adhered to the right side surface of the rotor 6. The rotor 6 is clamped between the left stator 20 and the right stator 23. The rotor 6 is driven by the moving shaft 1 to rotate. In FIG. 6, the number of pole pairs of a left air gap is 3 and the number of pole pairs of a right air gap is 2.

Embodiment 3

[0068] FIG. 7 is a cross sectional view of a double-stator combined linear electric machine combining two permanent magnet synchronous machines. An upper stator winding is wound in an upper stator 24. An upper air gap permanent magnet 25 is adhered to the upper side surface of the rotor 26. A lower stator winding is wound in a lower stator 28. A lower air gap permanent magnet 27 is adhered to the lower side surface of the rotor 26. In FIG. 7, the number of pole pairs of an upper air gap is 3 and the number of pole pairs of a lower air gap is 2.