Synchronous reluctance motor

Abstract

To improve conductivity on one side of an axial direction of a conductive member inserted into a flux barrier.SOLUTION: One embodiment of a synchronous reluctance motor has a flux barrier provided in each pole of a rotor core, and a conductive member branched from one side of an axial direction and located within the flux barriers different from each other.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a synchronous reluctance motor. [Background technology]

[0002] Patent Document 1 discloses a synchronous reluctance motor having a stator with a primary coil provided in a plurality of slots arranged on the outside of the rotor, and a secondary coil provided on the rotor, the secondary coil including a conductive bar arranged at a distance of 5% to 10% of the radius of the rotor from the outer periphery of the rotor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6548042 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the synchronous reluctance motor disclosed in Patent Document 1, both axial ends of the conductive bars inserted into the flux barrier slits are fastened to the outer surfaces of the end plates by L-shaped metal fittings. The method of connecting the conductive bars with L-shaped metal fittings on both axial ends of the conductive bars may result in a decrease in conductivity at the connection points between the conductive bars. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a synchronous reluctance motor that is capable of improving the conductivity on one axial side of a conductive member inserted into a flux barrier. [Means for solving the problem]

[0005] One aspect of a synchronous reluctance motor according to the present invention includes a flux barrier provided at each pole of a rotor core, and conductive members branched from one axial side and positioned within different flux barriers. [Effects of the Invention]

[0006] According to the present invention, it is possible to improve the conductivity on one axial side of the conductive member inserted into the flux barrier. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view showing the configuration of a synchronous reluctance motor according to a first embodiment. [Figure 2A] FIG. 2A is a perspective view of the configuration of the synchronous reluctance motor according to the first embodiment, as viewed from one axial side. [Figure 2B] FIG. 2B is a perspective view of the configuration of the synchronous reluctance motor according to the first embodiment, as viewed from the other axial side. [Figure 2C] FIG. 2C is a cross-sectional view showing the configuration of the synchronous reluctance motor according to the first embodiment taken along the axial direction. [Figure 3A] 3A is a cross-sectional view showing a configuration in which no conductive member is inserted in the flux barrier of one pole of the synchronous reluctance motor of FIG. 1. FIG. [Figure 3B] 3B is a cross-sectional view showing a configuration in which a conductive member is inserted into one flux barrier of one pole of the synchronous reluctance motor of FIG. 1. FIG. [Figure 3C] 3C is a cross-sectional view showing a configuration in which a conductive member is inserted into two flux barriers of one pole of the synchronous reluctance motor of FIG. 1. FIG. [Figure 4A] FIG. 4A is a perspective view of the configuration of a synchronous reluctance motor according to the second embodiment, as viewed from one axial side. [Figure 4B] FIG. 4B is a perspective view of the configuration of the synchronous reluctance motor according to the second embodiment, as viewed from the other axial side. [Figure 5A] FIG. 5A is a perspective view showing a state before conductive members are inserted into the flux barriers of each pole of a synchronous reluctance motor according to a third embodiment. [Figure 5B]FIG. 5B is a perspective view showing a state after conductive members have been inserted into the flux barriers of each pole of the synchronous reluctance motor according to the third embodiment. [Figure 5C] FIG. 5C is a perspective view showing the state after the end rings of the synchronous reluctance motor according to the third embodiment have been formed. [Figure 6A] FIG. 6A is a perspective view showing a state after conductive members have been inserted into the flux barriers of each pole of a synchronous reluctance motor according to a fourth embodiment. [Figure 6B] FIG. 6B is a perspective view showing a state after the conductive members inserted into the flux barriers of the poles of the synchronous reluctance motor according to the fourth embodiment have been bent. [Figure 6C] FIG. 6C is a perspective view showing the state after the end rings of the synchronous reluctance motor according to the fourth embodiment have been formed. [Figure 7A] FIG. 7A is a perspective view showing a state before conductive members are inserted into the flux barriers of each pole of a synchronous reluctance motor according to a fifth embodiment. [Figure 7B] FIG. 7B is a perspective view showing a state after conductive members have been inserted into the flux barriers of each pole of the synchronous reluctance motor according to the fifth embodiment. [Figure 7C] FIG. 7C is a perspective view showing the state after the end rings of the synchronous reluctance motor according to the fifth embodiment have been formed. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the present invention, and not all combinations of features described in the embodiments are necessarily essential to the configuration of the present invention. The configuration of the embodiments may be modified or changed as appropriate depending on the specifications of the device to which the present invention is applied and various conditions (such as usage conditions and usage environment). The technical scope of the present invention is determined by the claims and is not limited by the individual embodiments described below. Furthermore, the drawings used in the following description may differ in scale and shape from the actual structure to make each configuration easier to understand.

[0009] In the following embodiments, the number of poles P of the synchronous reluctance motor is four, but the number of poles P of the synchronous reluctance motor may be two or more.

[0010] Fig. 1 is a cross-sectional view showing the configuration of a synchronous reluctance motor according to the first embodiment, Fig. 2A is a perspective view of the configuration of the synchronous reluctance motor according to the first embodiment as seen from one axial side, Fig. 2B is a perspective view of the configuration of the synchronous reluctance motor according to the first embodiment as seen from the other axial side, and Fig. 2C is a cross-sectional view showing the configuration of the synchronous reluctance motor according to the first embodiment taken along the axial direction. Note that Fig. 1 shows the configuration taken along line A1-A1 in Fig. 2C. Also, Fig. 2A(a) is a perspective view showing the state of the rotor after insertion of conductive members, and Figs. 2A(b) and 2A(c) are perspective views showing the shape before insertion of conductive members.

[0011] 1 and 2A to 2C, the synchronous reluctance motor SynRM includes a stator 1 and a rotor 2A. A shaft 3 is inserted into the rotor 2A in the axial direction of a rotation axis C1. The rotor 2A can rotate around the shaft 3 based on the rotating magnetic field generated by the stator 1. At this time, the rotor core of the rotor 2A is magnetized along the magnetic field generated by the stator 1. The rotor core receives a force so that the polarity of the rotor core is aligned with the magnetic field generated by the stator 1, allowing the rotor 2A to rotate. The rotor core can be formed by laminating thin plate-like magnetic material, for example, ferromagnetic material such as silicon steel plate, into a cylindrical shape. In this case, to rotate the rotor 2A based on the rotating magnetic field generated by the stator 1, it is not necessary to pass an induced current through the rotor core, nor is it necessary to use a rare-earth magnet in the rotor core. This makes it possible to reduce losses in the synchronous reluctance motor SynRM, making it possible to improve efficiency compared to induction motors, and also eliminating the need for rare metals such as cobalt, samarium, or neodymium, making it possible to flexibly respond to demand for synchronous reluctance motors SynRM.

[0012] The stator 1 has slots 11 arranged at equal intervals on the inner periphery, and teeth 12 provided between the slots 11. A winding 13 is wound around each tooth 12.

[0013] The rotor core of the rotor 2A has flux segments 21 arranged on each pole, and the flux segments 21 of each pole are separated by flux barriers 22. In this case, each of the flux barriers 22 of each pole can be configured as a slit-shaped gap adjacent to the flux segment 21. On the q axis of each pole, each of the flux barriers 22 of each pole can extend in a direction perpendicular to the q axis and bend toward the inner periphery of the slot 11 along the d axis. Note that the q axis is located at the center of the magnetic pole of each pole, and the d axis is located at the boundary between the magnetic poles of each pole. In this case, the magnetic field generated when a current flows through the winding 13 is guided along the flux segments 21 via the tips of the teeth 12, and polarity can be imparted to the flux segments 21.

[0014] The synchronous reluctance motor SynRM also includes conductive members B1 to B4 and end rings E1 and E2. Each of the conductive members B1 to B4 branches off from one axial side and is located in a different flux barrier 22. In this specification, the one axial side of the rotating shaft C1 or the other axial side of the rotating shaft C1 may be simply referred to as the one axial side or the other axial side.

[0015] In this case, each of the conductive members B1 to B4 can be positioned within multiple flux barriers 22 of the same polarity. FIG. 2A shows an example in which each of the conductive members B1 to B4 is positioned within two flux barriers 22 of the same polarity. Here, each of the conductive members B1 to B4 can be folded back on one axial side of each polarity so that it can be inserted into two flux barriers 22 of the same polarity while connected on one axial side. In this case, each of the conductive members B1 to B4 can be bent perpendicular to the axial direction on one axial side. The bending position on one axial side of each of the conductive members B1 to B4 can be set to a position that straddles the flux segment 21 between the different flux barriers 22 in which each of the conductive members B1 to B4 is positioned. In this case, each of the conductive members B1 to B4 can be bent, for example, in a hairpin shape. It is preferable that each of the conductive members B1 to B4 has a rectangular cross-sectional shape and is made of copper. In this case, each of the conductive members B1 to B4 can be formed by bending a copper bar. Furthermore, the axial length of each of the conductive members B1 to B4 can be set so that after each of the conductive members B1 to B4 is inserted into the flux barrier 22, each of the conductive members B1 to B4 protrudes on the other axial side.

[0016] The end ring E1 is provided on one axial side of the conductive members B1-B4, and the end ring E2 is provided on the other axial side of the conductive members B1-B4. The end rings E1 and E2 short-circuit the one axial side and the other axial side of the conductive members B1-B4 and can fix the conductive members B1-B4. The amount of protrusion of each conductive member B1-B4 on one axial side can be set so that the branching point of each conductive member B1-B4 is accommodated within the end ring E1, and the amount of protrusion of each conductive member B1-B4 on the other axial side can be set so that the end of each conductive member B1-B4 is accommodated within the end ring E2. The end rings E1 and E2 can also be used for dynamic balancing. In this case, the end rings E1 and E2 may have protrusions 31 and 32 on their outer surfaces that protrude in the axial direction of the rotation axis C1 to lock the screws of the end rings E1 and E2 and balance the rotor 2A. The end rings E1 and E2 can be made, for example, by aluminum casting.

[0017] Here, by branching each of the conductive members B1 to B4 on one axial side, it is possible to eliminate joints between each of the conductive members B1 to B4 on one axial side while enabling each of the conductive members B1 to B4 to be inserted into different flux barriers 22. Therefore, it is possible to improve the conductivity on one axial side of each of the conductive members B1 to B4 inserted into different flux barriers 22 while suppressing a decrease in workability when inserting each of the conductive members B1 to B4 into different flux barriers 22.

[0018] Furthermore, by folding back each of the conductive members B1 to B4 on one axial side, it becomes possible to insert each of the conductive members B1 to B4 into different flux barriers 22 with the conductive members short-circuited on one axial side, and there is no need to use dissimilar metals to connect each of the conductive members B1 to B4 on one axial side, which makes it possible to prevent a decrease in the conductivity of each of the conductive members B1 to B4 on one axial side while suppressing increases in costs.

[0019] Furthermore, by setting the bending position on one axial side of each of the conductive members B1 to B4 to a position that straddles the flux segment 21 between the different flux barriers 22 in which the conductive members B1 to B4 are located, the conductive members can be maintained in a short-circuited state on one axial side, and each of the conductive members B1 to B4 can be inserted into the different flux barriers 22 without deforming the flux segment 21 and each of the conductive members B1 to B4. Therefore, without reducing the ease of inserting each of the conductive members B1 to B4 into the different flux barriers 22, it is possible to improve the conductivity on one axial side of each of the conductive members B1 to B4 inserted into the different flux barriers 22, and to suppress a decrease in the efficiency of the synchronous reluctance motor SynRM.

[0020] Furthermore, by providing each of the conductive members B1 to B4 within a plurality of flux barriers 22 of the same pole, it is possible to maintain a state in which each of the conductive members B1 to B4 is short-circuited on one axial side, while increasing the number of each of the conductive members B1 to B4 inserted into different flux barriers 22. This makes it possible to improve the starting capability while eliminating the need for an inverter for starting, enables the synchronous reluctance motor SynRM to be operated on a commercial power supply, and maintains higher efficiency than an induction motor, thereby expanding the range of applications of the synchronous reluctance motor SynRM.

[0021] Furthermore, by making the cross-sectional shape of each of the conductive members B1 to B4 rectangular, it is possible to easily bend each of the conductive members B1 to B4 on one axial side while making the thickness of each of the conductive members B1 to B4 match the spacing between the flux segments 21 at which the flux barriers 22 are located. This makes it possible to increase the conductivity of each of the conductive members B1 to B4 inserted into the flux barriers 22 without reducing the ease of inserting each of the conductive members B1 to B4 into the different flux barriers 22, thereby improving the starting capability while eliminating the need for an inverter for starting.

[0022] Furthermore, by using copper as the material for each of the conductive members B1 to B4, it becomes possible to use a metal with the second highest conductivity after silver as the material for each of the conductive members B1 to B4, and it is possible to suppress cost increases compared to when silver is used.

[0023] Furthermore, by short-circuiting one axial side and the other axial side of each of the conductive members B1 to B4 via end rings E1, E2, it is possible to add a squirrel-cage conductor structure to the rotor 2A while maintaining higher efficiency than an induction motor. Therefore, if the synchronous reluctance motor SynRM is connected to a commercial power supply in the same way as an induction motor, it can be started, thereby expanding the range of applications of the synchronous reluctance motor SynRM.

[0024] Furthermore, by forming each end ring E1, E2 by aluminum casting, molten aluminum is poured into a mold and solidified, thereby shorting one axial side and the other axial side of the conductive members via the end rings E1, E2, and fixing each conductive member B1-B4. This makes it possible to add a squirrel-cage conductor structure to the rotor 2A while suppressing cost increases, and improves the conductivity of the squirrel-cage conductor structure added to the rotor 2A. As a result, the starting capability can be improved without reducing the efficiency of the synchronous reluctance motor SynRM, and the range of applications of the synchronous reluctance motor SynRM can be expanded.

[0025] 3A is a cross-sectional view showing a configuration in which no conductive member is inserted into the flux barrier of one pole of the synchronous reluctance motor of FIG. 1; FIG. 3B is a cross-sectional view showing a configuration in which a conductive member is inserted into one flux barrier of one pole of the synchronous reluctance motor of FIG. 1; and FIG. 3C is a cross-sectional view showing a configuration in which conductive members are inserted into two flux barriers of one pole of the synchronous reluctance motor of FIG. 1.

[0026] In the rotor core of the rotor 2A'' in FIG. 3A, no conductive member is inserted into the flux barrier 22 of each pole. In the rotor core of the rotor 2A' in FIG. 3B, a conductive member B1' is inserted into one flux barrier 22 of each pole. In the rotor core of the rotor 2A in FIG. 3C, a conductive member B1 is inserted into two flux barriers 22 of each pole.

[0027] Simulations were performed on the efficiency and starting capability of the configurations shown in Figures 3A to 3C. The configuration shown in Figure 3B improved the starting capability by 2.2 times compared to the configuration shown in Figure 3A without changing the efficiency. The configuration shown in Figure 3C improved the starting capability by 2.6 times compared to the configuration shown in Figure 3A without changing the efficiency.

[0028] In the above-described embodiment, an example was taken in which the rotor core had four poles and each of the conductive members B1 to B4 had two branches. However, where P is the number of poles of the rotor core and N is (the number of barrier channels for each pole - 1), the number of branches M of the conductive member on one axial side may be 2≦M≦P·N. This makes it possible to set the number of branches of the conductive member on one axial side according to the number of poles and the number of barrier channels, and to insert the conductive members short-circuited on one axial side into different flux barriers.

[0029] Fig. 4A is a perspective view of the configuration of a synchronous reluctance motor according to a second embodiment, as seen from one axial side, and Fig. 4B is a perspective view of the configuration of a synchronous reluctance motor according to the second embodiment, as seen from the other axial side. Fig. 4A(a) is a perspective view showing the state of the rotor after the conductive members have been inserted, and Fig. 4A(b) is a perspective view showing the shape before the conductive members have been inserted.

[0030] 4A and 4B, this synchronous reluctance motor includes a rotor 2B in place of rotor 2A in Fig. 1. Rotor 2B includes conductive members B11 and B12 in place of conductive members B1 to B4 in Fig. 2A. Other than that, rotor 2B can be configured similarly to rotor 2A.

[0031] Each of the conductive members B11 and B12 can be positioned within multiple flux barriers 22 of different poles. FIG. 4A illustrates an example in which each of the conductive members B11 and B12 is positioned within one flux barrier 22 of two different poles. Here, each of the conductive members B11 and B12 can be folded back on one axial side of each pole so that it can be inserted into one flux barrier 22 of two different poles while connected on one axial side. In this case, each of the conductive members B11 and B12 can be folded perpendicular to the axial direction on one axial side. The folding position on one axial side of each of the conductive members B11 and B12 can be set to a position that straddles the flux segment 21 between the different flux barriers 22 where the conductive members B11 and B12 are positioned. It is preferable that each of the conductive members B11 and B12 positioned within the flux barrier 22 has a rectangular cross-sectional shape and is made of copper.

[0032] Here, by providing each conductive member B11, B12 inside a plurality of flux barriers 22 of mutually different polarities, it is possible to maintain a state in which each conductive member B11, B12 is short-circuited on one axial side, while increasing the number of conductive members B11, B12 inserted into mutually different flux barriers 22. This makes it possible to improve starting capability while eliminating the need for an inverter for starting, enables the synchronous reluctance motor to be operated on a commercial power supply, and maintains higher efficiency than an induction motor, thereby expanding the range of application of synchronous reluctance motors.

[0033] Figure 5A is a perspective view showing the state before conductive members are inserted into the flux barriers of each pole of the synchronous reluctance motor of the third embodiment, Figure 5B is a perspective view showing the state after conductive members have been inserted into the flux barriers of each pole of the synchronous reluctance motor of the third embodiment, and Figure 5C is a perspective view showing the state after the end rings of the synchronous reluctance motor of the third embodiment have been formed.

[0034] 5A to 5C, this synchronous reluctance motor includes rotor 2C in place of rotor 2A in Fig. 1. Rotor 2C includes conductive members B21 to B24 and end rings E21 and E22 in place of conductive members B1 to B4 and end rings E1 and E2 in Fig. 2A. Other than that, rotor 2C can be configured in the same way as rotor 2A.

[0035] Each of the conductive members B21 to B24 can be positioned within a plurality of flux barriers 22 of mutually different polarities. FIG. 5B illustrates an example in which each of the conductive members B21 to B24 is positioned within two flux barriers 22 of mutually different polarities. Here, each of the conductive members B21 to B24 can be folded back on one axial side of each pole so that it can be inserted into two flux barriers 22 of mutually different polarities while connected on one axial side. In this case, each of the conductive members B21 to B24 can be bent perpendicular to the axial direction on one axial side, as shown in FIG. 5A. The bending position on one axial side of each of the conductive members B21 to B24 can be set to a position that straddles the flux segment 21 between the different flux barriers 22 in which each of the conductive members B21 to B24 is positioned, as shown in FIG. 5B. In this case, each of the conductive members B21 to B24 can have two conductive bars that are inserted into two flux barriers 22 of mutually different polarities. Two different conductive bars of conductive members B21 to B24 are inserted into the same flux barrier 22 of each pole. It is preferable that the cross-sectional shape of each of the conductive members B21 to B24 located in the flux barrier 22 is rectangular, and that each of the conductive members B21 to B24 is made of copper.

[0036] Here, the conductive bars of each of the conductive members B21 to B24 can be made thinner by inserting the conductive bars of two different conductive members B21 to B24 into the same flux barrier 22 of each pole. This allows each of the conductive members B21 to B24 to be manufactured by bending a single conductive bar, thereby reducing the cost of manufacturing the conductive members B21 to B24.

[0037] 5C, an end ring E21 is provided on one axial side of the conductive members B21 to B24, and an end ring E22 is provided on the other axial side of the conductive members B21 to B24. In this case, the end rings E21 and E22 short-circuit the one axial side and the other axial side of the conductive members B21 to B24, and can fix the conductive members B21 to B24.

[0038] The end rings E21 and E22 can be produced by inserting conductive members B21 to B24 into a plurality of flux barriers 22 of different polarities, and then casting the conductive members. The conductive members B21 to B24 may be coated with a metal to improve adhesion between the end rings E21 and E22 and the conductive members B21 to B24. The positions of the metal coating on the conductive members B21 to B24 should include the contact positions between each of the conductive members B21 to B24 and the end rings E21 and E22. The coating method may be, for example, plating or thermal spraying. The metal is, for example, silver.

[0039] Here, by providing each of the conductive members B21 to B24 within a plurality of flux barriers 22 of mutually different polarities, it is possible to maintain a state in which each of the conductive members B21 to B24 is short-circuited on one axial side, while increasing the number of conductive members B21 to B24 inserted within mutually different flux barriers 22. This makes it possible to improve starting capability while eliminating the need for an inverter for starting, enables the synchronous reluctance motor to be operated on a commercial power supply, and maintains higher efficiency than an induction motor, thereby expanding the range of application of the synchronous reluctance motor.

[0040] FIG. 6A is a perspective view showing the state after conductive members have been inserted into the flux barriers of each pole of the synchronous reluctance motor of the fourth embodiment, FIG. 6B is a perspective view showing the state after the conductive members inserted into the flux barriers of each pole of the synchronous reluctance motor of the fourth embodiment have been bent, and FIG. 6C is a perspective view showing the state after the end rings of the synchronous reluctance motor of the fourth embodiment have been formed.

[0041] 6A to 6C, this synchronous reluctance motor includes rotor 2D in place of rotor 2C of Figures 5A to 5C. Rotor 2D includes conductive members B31 to B34 and end rings E31 and E32 in place of conductive members B21 to B24 and end rings E21 and E22 of Figures 5A to 5C. Other than that, rotor 2D can be configured similarly to rotor 2C.

[0042] The conductive members B31 to B34 differ from the conductive members B21 to B24 in that, as shown in Fig. 6B, the ends of the protruding portions of the conductive members B31 to B34 on the other axial side are bent toward each other. In this case, as shown in Fig. 6A, the axial length of the conductive bar of each of the conductive members B31 to B34 can be made longer than the axial length of the conductive bar of each of the conductive members B21 to B24. Then, after the straight conductive bar of each of the conductive members B31 to B34 is inserted into the flux barrier 22, the ends of the conductive bar on the other axial side of each of the conductive members B31 to B34 can be bent as shown in Fig. 6B.

[0043] 6C, an end ring E31 is provided on one axial side of the conductive members B31 to B34, and an end ring E32 is provided on the other axial side of the conductive members B31 to B34. In this case, the end rings E31 and E32 short-circuit the one axial side and the other axial side of the conductive members B31 to B34 and can fix the conductive members B31 to B34. The end rings E31 and E32 can be made by aluminum casting after the conductive members B31 to B34 are inserted into multiple flux barriers 22 of different polarities.

[0044] Here, by bending the ends of the protruding portions of each conductive member B31 to B34 in a direction that brings them closer to each other, the conductivity of the connection of the conductive members B31 to B34 on the other axial side inserted into different flux barriers 22 can be improved without reducing the ease of insertion of each conductive member B31 to B34 into different flux barriers 22.

[0045] Figure 7A is a perspective view showing the state before conductive members are inserted into the flux barriers of each pole of the synchronous reluctance motor of the fifth embodiment, Figure 7B is a perspective view showing the state after conductive members have been inserted into the flux barriers of each pole of the synchronous reluctance motor of the fifth embodiment, and Figure 7C is a perspective view showing the state after the end rings of the synchronous reluctance motor of the fifth embodiment have been formed.

[0046] 7A to 7C, this synchronous reluctance motor includes rotor 2E instead of rotor 2C of Figures 5A to 5C. Rotor 2E includes conductive members B41 to B44 and end rings E41 and E42 instead of conductive members B21 to B24 and end rings E21 and E22 of Figures 5A to 5C. In all other respects, rotor 2E can be configured similarly to rotor 2C.

[0047] The conductive members B41 to B44 differ from the conductive members B21 to B24 in that, while the conductive members B21 to B24 have two branches on one axial side, the conductive members B41 to B44 have four branches on one axial side, as shown in FIG. 7A. In this case, the conductive members B41 to B44 can be inserted into four different flux barriers 22. FIGS. 7A to 7C show an example in which the conductive members B41 to B44 are positioned in two flux barriers 22 for two different poles. In this case, the branch positions on one axial side of each of the conductive members B41 to B44 can be set to positions that straddle the flux segments 21 between the different flux barriers 22 in which the conductive members B41 to B44 are positioned. In this case, the conductive members B41 to B44 may be configured, for example, in a comb shape. Each of the conductive members B41 to B44 may be made by punching a copper plate or by welding a copper bar, for example.

[0048] 7C, an end ring E41 is provided on one axial side of the conductive members B41-B44, and an end ring E42 is provided on the other axial side of the conductive members B41-B44. In this case, the end rings E41 and E42 short-circuit the one axial side and the other axial side of the conductive members B41-B44 and can fix the conductive members B41-B44. The end rings E41 and E42 can be made by aluminum casting after the conductive members B41-B44 are inserted into multiple flux barriers 42 of different polarities.

[0049] Here, by increasing the number of branches on one axial side of each conductive member B41 to B44, it is possible to improve the conductivity of the cage-type conductor structure added to the rotor 2E without reducing the ease of inserting each conductive member B41 to B44 into different flux barriers 22, thereby improving the starting capability. [Explanation of symbols]

[0050] SynRM synchronous reluctance motor, 1 stator, 2A rotor, 3 shaft, 11 slot, 12 teeth, 13 winding, 21 flux segment, 22 flux barrier, B1 to B4 conductive members

Claims

1. a flux barrier provided on each pole of the rotor core; a plurality of conductive members; A synchronous reluctance motor characterized in that each conductive member has multiple branch portions branching from one axial side of the rotor, and the multiple branch portions of each conductive member are inserted into different flux barriers.

2. 2. The synchronous reluctance motor according to claim 1, wherein the number M of the branch portions of the conductive member satisfies 2≦M≦P·N, where P is the number of poles of the rotor core and N is (the number of barrier channels of each pole minus 1).

3. A synchronous reluctance motor as described in claim 1, characterized in that each conductive member has two branch portions by being folded back on one side in the axial direction.

4. Each conductive member has the two branch portions and a connecting portion located on one side of the axial direction and extending in a direction perpendicular to the axial direction to connect the two branch portions; 4. The synchronous reluctance motor according to claim 3, wherein the connecting portions of the conductive members are located at positions that straddle the flux segments between the different flux barriers in which the conductive members are located.

5. A synchronous reluctance motor as described in any one of claims 1 to 4, characterized in that the multiple branch portions of each conductive member are located within multiple flux barriers of the same pole.

6. 6. The synchronous reluctance motor according to claim 1, wherein the plurality of branched portions of the conductive member are located within a plurality of flux barriers of mutually different poles.

7. A synchronous reluctance motor as described in any one of claims 1 to 6, characterized in that the cross-sectional shape of each conductive member is rectangular.

8. The two branch portions of each conductive member protrude from the flux barrier on the other side in the axial direction, 8. The synchronous reluctance motor according to claim 1, wherein the protruding portions of the two branches are bent so as to approach each other.

9. 9. A synchronous reluctance motor according to claim 1, wherein the conductive member is made of copper.

10. 10. The synchronous reluctance motor according to claim 1, further comprising an end ring provided at least at one end in the axial direction of the conductive members to fix the plurality of conductive members.

11. 11. The synchronous reluctance motor according to claim 10, wherein the end rings are provided on one axial side and the other axial side of the conductive members, and the one axial side and the other axial side of the plurality of conductive members are short-circuited via the end rings.

12. 12. The synchronous reluctance motor according to claim 10, wherein the end rings are formed by aluminum casting.

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