JP2015023767A - Synchronous reluctance motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synchronous reluctance motor which implements self-excitation to be functioned by collecting loss energy and improves torque through high-efficiency rotation.SOLUTION: A synchronous reluctance motor 10 comprises a stator 11 including an armature pole coil 14 for inputting driving currents of three phases and a rotor 21 which includes a plurality of rotor teeth 22 and is rotated by a main rotation force with interlinkage of a magnetic flux generated in the armature pole coil. The rotor includes: an inductor pole coil 27 in which an induction current is generated by a spatial higher harmonic component of a magnetic flux interlinked from the stator side to the rotor side; a diode for rectifying the induction current generated in the inductor pole coil; an electromagnet pole coil 28 which is self-excited with the induction current rectified by the diode as a field current and generates an electromagnetic force for supporting the main rotation force; and permanent magnets 37A and 37B embedded so as to cooperate with the main rotation force by operating a magnetic force upon the stator.

Description

  The present invention relates to a synchronous reluctance motor, and more particularly to a motor that has a self-excitation function and realizes high-efficiency rotation.

Synchronous reluctance motors are mounted as drive sources in various drive devices. A reluctance motor is difficult to obtain a large torque in the case of a type that uses only reluctance torque, compared to a motor (electric motor) that is driven by embedding a permanent magnet on the rotor side and using magnet torque. There is a problem.
In particular, when mounted on hybrid electric vehicles and electric vehicles that require large torque, a neodymium magnet with strong magnetic force is used to effectively use reluctance torque along with magnet torque. A motor employing an IPM (Interior Permanent Magnet) structure in which a permanent magnet such as (Neodymium magnet) is embedded in a V-shape in a rotor (rotor) is often used.

Incidentally, it has been proposed to improve the efficiency of a reluctance motor by adopting a self-excitation function as described in Non-Patent Document 1, for example. As an in-vehicle motor, improvement in characteristics such as torque improvement in a reluctance motor that can be manufactured at low cost is desired.
In the self-excitation method described in Non-Patent Document 1, a self-magnetic flux having a frequency higher than the fundamental frequency of the drive current supplied to the armature pole coil on the stator side is linked to the rotor side and arranged on the rotor side. An induction current is generated in the exciting coil. In this self-excitation system, the induced current is rectified by half-wave and then supplied (returned) to the self-excitation coil so that the self-excitation coil functions as an electromagnet coil.

However, in the self-excitation function described in Non-Patent Document 1, since the self-excitation coil is also used as an electromagnet pole coil, magnetic interference occurs and induction current can be generated efficiently. In addition, the generated electromagnetic force is weakened.
In the structure described in Non-Patent Document 1, the self-excitation coil is disposed up to a deep part separated from the outer surface of the rotor, but the high-frequency component (space harmonic component) of the magnetic flux enters (links) into the rotor deep part. And only a very small induced current can be generated in the self-excitation coil.
Patent Document 1 also proposes a self-excitation motor, but similarly, it cannot generate an induced current efficiently and has the same problem.
Further, Patent Document 2 proposes that an excitation current is generated in the self-excitation coil on the rotor side by separately inputting a high-frequency current into the coil on the stator side, but it is necessary to input excitation energy externally. Yes, high-efficiency drive cannot be desired (decrease in efficiency is inevitable).

Japanese Patent Laid-Open No. 10-271881 JP 2010-22185 A

Sakutaro Nonaka “Self-Excited Single-Phase Synchronous Motor” The Journal of the Institute of Electrical Engineers of Japan, Vol. 78, 842, November 1958, p. 18-26

  SUMMARY OF THE INVENTION An object of the present invention is to provide a synchronous reluctance motor that realizes self-excitation that functions by recovering lost energy, and has improved torque by high efficiency rotation.

  According to a first aspect of the present invention, a stator provided with an armature pole coil for inputting a plurality of phases of drive currents and a plurality of main torque received by interlinking magnetic fluxes generated in the armature pole coil. A synchronous reluctance motor including a salient pole, and a spatial harmonic component superimposed on the magnetic flux generated by the armature pole coil is linked to the rotor side. An inductor pole coil disposed on the magnetic path and generating an induced current by a spatial harmonic component of the magnetic flux, a rectifier element for rectifying the induced current generated in the inductor pole coil, and rectified by the rectifier element An electromagnetic pole coil that generates an electromagnetic force as an auxiliary rotational force that assists the main rotational force by energizing the induced current as a field current and performing self-excitation, and a magnetic force on the stator It is characterized in that and a permanent magnet is embedded so as to cooperate with said main rotational force worked.

  According to a second aspect of the present invention, the rotor includes a plurality of rotor teeth extending toward an inner peripheral surface of the stator and facing the outer peripheral surface to the inner peripheral surface, and the inductor pole It is preferable that the coil is formed by being wound around the rotor teeth, and the permanent magnet is disposed in a rotor slot between the rotor teeth formed as a space for winding the inductor pole coil.

  According to a third aspect of the present invention, the rotor has an electromagnet core around which the electromagnet coil is wound around the bottom of the rotor slot, and the inductor pole coil is disposed on the outer peripheral side of the rotor. And it is suitable for the said electromagnet pole coil to be arrange | positioned at the rotating shaft side of the said rotor.

  According to a fourth aspect of the present invention, the electromagnet coil is installed so that the N poles and the S poles face each other with the rotor teeth interposed therebetween, and the permanent magnet is disposed in the rotor slot in the outer periphery of the rotor. It is preferable that it is installed on the surface side so as to form a loop-shaped magnetic flux that links with the gap between the stator and the inner peripheral surface as a magnetic path.

  According to a fifth aspect of the present invention, the rotor includes a support portion extending from the center of the bottom of the rotor slot toward the outer peripheral surface of the rotor, and an outer periphery of the rotor teeth positioned on both sides of the rotor slot. First and second extension portions each having a surface extending toward the inside of the rotor slot, and the permanent magnet is provided between each of the first and second extension portions and the support portion. The first and second permanent magnets are arranged so that the magnetization direction is opened in a V shape toward the outer peripheral surface side of the rotor. One end side of the first and second permanent magnets It is preferable that an N-pole and an S-pole be positioned on the outer peripheral surface side of the rotor to form a loop-shaped magnetic flux interlinking with a gap between the inner peripheral surface of the stator and a magnetic path.

As described above, according to the first aspect, the main rotational force is generated by interlinking the magnetic flux generated by the armature pole coil on the stator side with the salient pole on the rotor side. The spatial harmonic component superimposed on the rotor is linked to the rotor-side inductor pole coil to generate an induced current. The induced current is rectified by a rectifying element and supplied to the electromagnet coil as a field current (energized), so that the electromagnet pole coil generates an electromagnetic force (magnetic flux) to cooperate with the magnetic flux from the stator side. And an auxiliary rotational force for assisting the main rotational force can be generated to rotate the rotor side.
In addition, the rotor that rotates with the main rotational force and the auxiliary rotational force can be rotated with a greater force by the embedded permanent magnets cooperating with each other by applying a magnetic force to the stator.
Therefore, without separately supplying energy to the electromagnet pole coil on the rotor side, the permanent magnet can be used while utilizing the spatial harmonic component of the magnetic flux that has not been effectively used in the past (which has been a cause of iron loss). In cooperation with the magnetic force, the rotor can be rotated with high efficiency. At this time, the same current does not flow in the inductor pole coil and the electromagnet pole coil, so that they do not interfere with each other and cause a loss. As a result, the rotor can be rotated using the magnetic force of the permanent magnet while effectively recovering the lost energy to improve the torque of the synchronous reluctance motor.

According to said 2nd aspect, a permanent magnet is arrange | positioned in the rotor slot between rotor teeth. For this reason, it is possible to produce rotor teeth in a desired size and shape without affecting the presence or absence of permanent magnets to obtain the optimum salient pole ratio, and to avoid spatial harmonic components without being affected by permanent magnets. Can be interlinked. Therefore, the reluctance torque can be generated effectively.
In addition, since permanent magnets are arranged between the rotor teeth around which the inductor coil is wound, fluctuations in the magnetic flux in the circumferential direction of the outer peripheral surface of the rotor can be reduced without making a mere gap, and even between rotor teeth Can be linked to the magnetic flux. Therefore, the pulsation of torque for rotating the rotor can be reduced, and high-quality rotation can be realized.

According to said 3rd aspect, by winding an electromagnet coil around the electromagnet core of the rotor slot bottom part used as the rotating shaft side, the magnetic flux containing a spatial harmonic component is chain | stranded without being disturbed by the electromagnet pole coil. An inductor pole coil having a sufficient number of coil turns can be disposed on the outer peripheral surface side of the rotor that intersects.
Therefore, the spatial harmonic component of the magnetic flux can be collected effectively and efficiently, and the electromagnet torque can be generated effectively.

According to said 4th aspect, the electromagnet pole coil which makes the both ends of the electromagnet core of a rotor slot bottom part N pole and S pole can function as an electromagnet used as the positional relationship which becomes symmetrical on both sides of a rotor tooth. The magnetic flux linked to the stator side can be generated and guided using the rotor teeth as a magnetic path. Therefore, torque can be effectively generated by the rotor teeth.
Further, since the permanent magnet is located on the outer peripheral surface side between the rotor teeth and forms a loop-like magnetic path with the stator, the magnetic force contributes as the rotational force of the rotor. Therefore, the torque can be efficiently generated by effectively using the magnetic force of the permanent magnet.

According to the fifth aspect, the stator is disposed between the N pole and the S pole on one end side of the first and second permanent magnets installed so as to open in a V shape toward the outer peripheral surface side of the rotor. Since the magnetic flux interlinking in a loop shape is formed between the first and second permanent magnets, the magnetic flux interlinking with the stator is positively utilized. The magnetic flux can be linked by widely using the outer peripheral surface of the rotor. Therefore, torque can be generated without increasing pulsation. Further, when the first and second extension portions are connected, the change in the magnetic resistance between the stator teeth can be moderated to generate a higher quality torque.

FIG. 1 is a diagram showing an embodiment of a synchronous reluctance motor according to the present invention, and is a radial sectional view showing a schematic configuration thereof. FIG. 2 is a partially enlarged radial direction sectional view showing the schematic configuration. FIG. 3 is a conceptual diagram showing a magnetic flux path interlinking between the rotor and the stator. FIG. 4 is a model diagram showing an electromagnet pole coil and a permanent magnet in a rotor by an equivalent magnetic circuit. FIG. 5 is a circuit diagram of a simple model for easily explaining a circuit configuration in which an inductor pole coil and an electromagnet pole coil are connected via a diode. FIG. 6 is a graph showing an induced current waveform extracted from one inductor pole coil in the circuit shown in FIG. FIG. 7 is a graph showing an induced current waveform extracted from the other inductor pole coil different from FIG. 5 and inverted in the circuit shown in FIG. FIG. 8 is a graph showing a combined waveform in which the induced currents of FIGS. 6 and 7 are merged. FIG. 9 is a graph showing an increase in torque due to a field current obtained by the synchronous reluctance motor of the present embodiment. FIG. 10 is a diagram showing another aspect of the present embodiment, and is a perspective view in a state where a part thereof is cut out.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIGS. 1-9 is a figure for demonstrating the synchronous reluctance motor of one Embodiment based on this invention. Here, FIG. 2 is a radial sectional view of the synchronous reluctance motor, showing a mechanical angle of 60 degrees centered on the axis, and the mechanical angle of 60 degrees is periodically repeated in the circumferential direction. The structure is made.
(Basic structure of a general synchronous reluctance motor)
1 and 2, the synchronous reluctance motor 10 has a performance suitable for being mounted on a vehicle or in a wheel wheel as a drive source similar to an internal combustion engine in, for example, a hybrid vehicle or an electric vehicle. Unlike the above-mentioned Patent Document 2, as will be described later, it is manufactured in a structure that does not require energy input to the rotor from the outside.

A synchronous reluctance motor 10 includes a stator (stator) 11 formed in a substantially cylindrical shape, and a rotor (rotor) in which a rotation shaft that is rotatably accommodated in the stator 11 and coincides with an axis is fixed. 21.
The stator 11 has a plurality of salient poles extending in the radial direction so that the outer peripheral surface 22a of the rotor 21 (rotor teeth 22) faces the inner peripheral surface 12a via the gap G. Stator teeth 12 are evenly arranged in the circumferential direction. The stator teeth 12 are formed with an armature pole coil 14 by using a status lot 13 in a space formed between adjacent side surfaces and individually concentrating three-phase windings for each phase. . The stator teeth 12 function as electromagnets that generate magnetic flux that rotates the rotor 21 that is housed facing the armature pole coil 14 by inputting a drive current to the armature pole coil 14.
In the rotor 21, a plurality of rotor teeth (saliency poles) 22 formed in a salient pole shape extending in the radial direction in the same manner as the stator teeth 12 are equally arranged in the circumferential direction. The rotor teeth 22 are formed in such a manner that the outer circumferential surface 22a is appropriately close to the inner circumferential surface 12a of the stator teeth 12 at the time of relative rotation by making the number of the circumferential teeth different from that of the stator teeth 12.
Thus, the synchronous reluctance motor 10 causes the magnetic flux generated by energizing the armature pole coil 14 in the status lot 13 of the stator 11 to face the outer peripheral surface of the rotor teeth 22 facing the inner peripheral surface 12a of the stator teeth 12. The rotor 21 can be relatively rotated by a reluctance torque (main rotational force) that can make the magnetic path (magnetic coupling) through which the magnetic flux passes be shortest. As a result, the synchronous reluctance motor 10 can output, as mechanical energy, electrical energy that is energized and input from the rotary shaft that rotates integrally with the rotor 21 that rotates relative to the stator 11.

In the synchronous reluctance motor 10, a spatial harmonic component is superimposed on the magnetic flux interlinking from the inner peripheral surface 12 a of the stator tooth 12 to the outer peripheral surface 22 a of the rotor tooth 22. For this reason, on the rotor 21 side as well, an electromagnetic current can be obtained by generating an induced current in a built-in coil by using a change in magnetic flux density of a spatial harmonic component of a magnetic flux interlinking from the stator 11 side.
Specifically, at this time, the driving power of the fundamental frequency is supplied to the armature pole coil 14 of the stator 11 to rotate the rotor 21 (rotor teeth 22) with the main magnetic flux that fluctuates at the fundamental frequency. Even if the coil is simply arranged on the side, the interlinkage magnetic flux does not change and no induced current is generated.
On the other hand, the spatial harmonic component superimposed on the magnetic flux is linked to the rotor teeth 22 from the outer peripheral surface 22a side while temporally changing at a period different from the fundamental frequency. For this reason, the spatial harmonic component superimposed on the magnetic flux of the fundamental frequency can efficiently generate an induced current in the coil installed in the vicinity of the outer peripheral surface 22a of the rotor tooth 22 without inputting it separately. As a result, the spatial harmonic magnetic flux that causes iron loss can be recovered as energy for self-excitation.

  Here, in the above-mentioned Non-Patent Document 1, a self-excitation technique is proposed. The self-excitation technique described in Non-Patent Document 1 generates an induced current by winding a coil around the rotor teeth 22 so that a magnetic flux having a frequency higher than the fundamental frequency is linked to the rotor side coil. The induced current is half-wave rectified by a rectifying element (diode) and returned, so that the rotor-side coil functions as a self-excited electromagnet.

However, the self-excitation technique described in Non-Patent Document 1 has the following problems.
1. As the coil on the rotor side, it is also used as a coil that generates an induced current and a coil that flows the rectified induced current as a field current, so that magnetic interference occurs and the induced current cannot be generated efficiently. The magnetomotive force will be very small.
2. Even if the high-frequency component of higher-order magnetic flux higher than the fundamental frequency is linked to the rotor 21 (rotor teeth 22), it remains distributed in the vicinity of the outer peripheral surface 22a, so that a coil is disposed on the axial center side. Only a very small induced current is generated. Even if the rotor side coil is installed in the vicinity of the outer peripheral surface 22a of the rotor teeth 22, it is practically impossible. For example, even when a very small amount of a conducting wire with a small wire diameter is wound as a coil, the conductor resistance increases, and as a result, copper loss increases, making it difficult to function as an efficient electromagnet. Further, there is a concern that the rotor surface contacts the stator side.
3. If the coil on the stator 11 side is distributed winding, higher harmonics tend to be superimposed on the magnetic flux, and as described above, only a smaller induced current can be expected with the high frequency component of the higher magnetic flux. In short, distributed winding is inappropriate as a method of winding the coil.
4). Non-Patent Document 1 explains that the rotor side coil is excited with a harmonic magnetic flux twice the fundamental frequency, but the induced current generated by the second harmonic magnetic flux forms a valley when rectified and synthesized. . Further, since the induced current becomes larger as the time change of the magnetic flux is larger, a third-order harmonic magnetic flux that is not too high is more advantageous.

(Structure of the synchronous reluctance motor of this embodiment)
From this, the synchronous reluctance motor 10 uses the space formed between the adjacent side surfaces of the rotor teeth 22 as the rotor slot 23, and effectively uses the entire rotor teeth 22 as a core material for winding. The inductor pole coil 27 is arranged by winding and forming concentrated winding, and the electromagnet pole coil 28 is arranged on the bottom side of the rotor slot 23.
The inductor pole coil 27 generates an induced current by a spatial harmonic component (change in magnetic flux density) of the magnetic flux interlinking from the inner peripheral surface 12a of the stator tooth 12 to the outer peripheral surface 22a of the rotor tooth 22, and generates an electromagnetic pole coil. 28. The electromagnet pole coil 28 can generate magnetic flux (electromagnetic force) by self-exciting the induced current received from the inductor pole coil 27 as a field current.

As a result, the synchronous reluctance motor 10 generates an induction current that flows in the inductor pole coil 27 with a spatial harmonic component superimposed on the magnetic flux MG in addition to the magnetic flux MG generated by the armature pole coil 14 shown in FIG. 28 can receive and generate magnetic flux, and can be linked from the outer peripheral surface 22 a of the rotor tooth 22 to the inner peripheral surface 12 a of the stator tooth 12. For this reason, the reluctance torque (auxiliary rotational force) that the magnetic flux interlinked with the magnetic flux MG of the armature pole coil 14 that generates the main rotational force tries to minimize the passage magnetic path can be obtained. Relative rotation can be assisted.
As a result, the synchronous reluctance motor 10 cannot be used in the case of only the rotor teeth 22, and can recover and output the spatial harmonic component of the magnetic flux that has been a cause of loss as energy, Only the rotor slot 23 cannot generate a driving force, and torque ripple that has been generated can be reduced.

  Here, in the synchronous reluctance motor 10, the entire rotor 21 including the rotor teeth 22 adopts a laminated structure of electromagnetic steel plates (magnetic bodies), so that the magnetic permeability is increased and the magnetic flux is generated between the stator 11 and the stator 11. By interfacing with the inner periphery 12a of the stator teeth 12 via the air gap G that is as small as possible, more space harmonic magnetic fluxes are interlinked. In this synchronous reluctance motor 10, the direction of the magnetic flux passing through the rotor teeth 22 is the d-axis, and the direction magnetically orthogonal to the d-axis is the q-axis.

Specifically, the synchronous reluctance motor 10 is formed with a second rotor slot 33 that is located in the rotor 21 on the rotating shaft side of the rotor slot 23 and functions as a winding winding space. Yes. In this synchronous reluctance motor 10, the rotor 21 is centered on the rotation axis by forming a connecting portion 35 extending from the center of the bottom of the rotor slot 23 toward the rotation axis so as to divide the second rotor slot 33. Thus, the rotating body is configured to rotate. That is, the second rotor slot 33 is formed in a space located on both sides in the rotation direction of the connecting portion 35 on the back side of the rotor slot 23 and located on the rotating shaft side of the rotor teeth 22.
The synchronous reluctance motor 10 uses the core material (electromagnet core) 28a between the rotor slot 23 and the second rotor slot 33 as a core material (electromagnet core) 28a, and performs concentrated winding for each rotor slot 23 on both sides of the connecting portion 35. An electromagnet coil 28 is disposed on the bottom side of the coil.

Thus, by adopting the concentrated winding structure, the inductor pole coil 27 and the electromagnet pole coil 28 do not need to be wound in the circumferential direction over a plurality of slots, and can be miniaturized as a whole. . Further, the inductor pole coil 27 efficiently generates an induced current due to the linkage of the third-order spatial harmonic magnetic flux which is a lower order while reducing the copper loss loss on the primary side, and can be recovered. Energy can be increased.
Further, the inductor pole coil 27 is more effectively induced by using the third-order spatial harmonic magnetic flux than when using the second-order spatial harmonic magnetic flux described in Non-Patent Document 1 described above. A current can be generated. More specifically, the induced current can be recovered efficiently by using the third-order spatial harmonic magnetic flux rather than the second-order so as to increase the time change of the magnetic flux to a large current. Note that Non-Patent Document 1 shows a coil wound around a deep portion on the axial center side of the rotor, and does not take into account the interlinkage region of spatial harmonics, and does not have a structure that can be used effectively.

When the electromagnetic pole coil 28 receives the induced current (field current) from the inductor pole coil 27 and self-excites, the magnet pole coil 28 is magnetized perpendicular to the q axis in the rotor 21 as shown in FIG. 4 as an equivalent magnetic circuit. It functions as an electromagnet 28M in the directions D3 and D4. The electromagnet pole coil 28 functions so as to function as one electromagnet 28M by forming the N pole and S pole of the magnetic poles at both ends so as to be in a positional relationship in which they are continuously opposed to each other on the back side of the rotor slot 23. In addition, the N poles or the S poles are formed so as to face each other on the rotary shaft side of the rotor teeth 22.
As a result, as shown in FIG. 3, the magnetic flux interlinked from the stator teeth 12 of the stator 11 to the rotor teeth 22 of the rotor 21 positively uses the d axis in the electromagnet pole coil 28 (core material 28 a) as a magnetic path. After passing, it can pass through the adjacent rotor teeth 22 and be linked to the stator teeth 12. Further, the magnetic flux generated by the self-excitation of the electromagnet coil 28 can also be linked from the rotor tooth 22 to the stator tooth 12 through the magnetic path in the same direction. Therefore, the synchronous reluctance motor 10 can effectively generate reluctance torque that effectively rotates the rotor 21 in the counterclockwise direction.

The synchronous reluctance motor 10 includes first and second bridges (extension portions) in which the end portions in the rotation direction on the outer peripheral surface 22a side of the rotor teeth 22 are extended toward the inner side of the rotor slot 23. ) 32A and 32B and a support portion 34 formed by extending the bottom surface portion on the q-axis of the rotor slot 23 from the rotation axis center toward the outer peripheral surface, thereby supporting the permanent magnets 37A and 37B in a sandwiched manner. It is like that.
Specifically, the permanent magnets 37A and 37B are formed such that the thicknesses of the magnetization directions D1 and D2 between the N pole and the S pole are equal to the thickness in the direction perpendicular to the magnetization directions D1 and D2. It is formed in a block shape that is significantly thinner than a permanent magnet embedded in a rotor by a conventional IPM type motor.

The first and second bridges 32 </ b> A and 32 </ b> B on the outer peripheral surface side of the rotor 21 are formed with support slopes 32 s that face the center side of the rotor slot 23, and the support portion 34 on the rotating shaft side of the rotor 21 includes A support groove 34s for accommodating the permanent magnets 37A and 37B is formed facing the support slope 32s.
With this structure, the permanent magnets 37A and 37B are supported in such a manner that the magnetization directions D1 and D2 open in a V shape toward the outer peripheral surface side of the rotor 21 so that the permanent magnets 37A and 37B are fitted in the support grooves 34s and pressed by the support inclined surfaces 32s. Has been.

The support portion 34 is integrally formed with a thin plate reinforcing bridge 34b extending between the support grooves 34s toward the outer peripheral surface side (radial direction) of the rotor 21, and the first and second bridges 32A and 32B are integrally formed. A thin plate reinforcing bridge 32b that extends further to the inner side of the rotor slot 23 and bends toward the rotating shaft side and continues to the reinforcing bridge 34b is integrally formed.
With this structure, the first and second bridges 32A and 32B have a configuration in which the reinforcing bridge 32b is connected to the reinforcing bridge 34b so that the rotor slot 23 is left open to the outside. It can suppress that it deform | transforms with the centrifugal force etc. which are added at the time of rotation.
Since the reinforcing bridges 32b and 34b are formed in a thin plate shape, the amount of magnetic flux flowing from the stator 11 side can be reduced, and the reinforcing bridge 32b increases the magnetic resistance to the stator 11 on the outer peripheral surface side. A groove shape 32 </ b> D is provided to restrict the flow of magnetic flux from the stator 11.
Further, the reinforcement bridges 32b and 34b are provided with permanent magnets 37A and 37B having high magnetic resistance, so that the magnetic independence with respect to the rotor teeth 22 is enhanced, and the reduction of the salient pole ratio of the rotor teeth 22 is suppressed. However, the permanent magnets 37A and 37B are arranged in the rotor slot 23 with high reliability.

Further, the permanent magnets 37A and 37B are installed so as to have the same number of poles as the number of sets of the electromagnet coil 28 for each rotor slot 23. As shown in FIG. 3 and FIG. N poles and S poles are alternately and continuously provided on the support 34 side so that D2 is aligned with the linkage direction of the magnetic flux promoted by the electromagnet pole coil 28 (depending on the winding direction of the electromagnet pole coil 28). It is installed so as to form a loop-shaped magnetic flux.
As shown in FIG. 3, the magnetic flux passing near the permanent magnets 37A and 37B causes the reinforcing bridge 32b to function as an iron core that forms a loop-shaped magnetic path located between the q-axis and the d-axis, A path that links from the stator 11 side to the rotor 21 side via the gap G and then returns to the stator 11 side is selected again to generate reluctance torque effectively.
At this time, the magnetic force (magnetic flux) of the permanent magnets 37A and 37B can also be linked from the rotor 21 side to the stator 11 side via the gap G to generate magnet torque that acts in the circumferential direction, and the rotor 21 rotates. The reluctance torque to be generated can be assisted.

  As a result, the magnetic flux interlinked from the stator 11 to the rotor 21 is also effectively magnetically coupled by actively returning the stator teeth 12 from the stator teeth 12 to the rotor teeth 22 even in the region where the rotor slots 23 are arranged. It is possible to reduce the pulsation caused by the magnetic resistance, and to generate the electromagnetic force in the circumferential direction over the entire circumference and efficiently rotate it counterclockwise with high quality and high torque. The permanent magnets 37A and 37B are sufficient in magnetic force for promoting the direction of linkage of the magnetic flux from the stator 11 to the rotor 21, so that a very small amount is sufficient as compared with the conventional IPM motor. That is, the permanent magnets 37A and 37B are not limited to neodymium magnets having a large magnetic force, but may be appropriately selected from the types of permanent magnets such as ferrite magnets and alnico magnets.

  As shown in FIG. 5, the electromagnet pole coil 28 has diodes 29 (29A, 29A, 27B, 27A, 27B) connected to both ends of the series-connected inductor pole coils 27 (27A, 27B). 29B). The number of the diodes 29 used is reduced by making the electromagnet coils 28 all in series even when the inductor coil 27 and the electromagnet coils 28 (28A, 28B) are multipolarized. In order to avoid mass use, this diode 29 does not form a general H-bridge type full-wave rectifier circuit, but is wired so as to have a phase difference of 180 degrees to invert one induced current. Thus, a neutral-point clamped half-wave rectifier circuit that forms a half-wave rectified output is formed.

Thereby, in the synchronous reluctance motor 10, the inductor pole coil 27 is changed from the inner peripheral surface 12a of the stator teeth 12 to the outer peripheral surface 22a of the rotor teeth 22 from the core material 27a (rotor teeth 22) of the electromagnetic steel plate having high magnetic permeability. It is possible to efficiently generate and recover the induced current by passing the spatial harmonic component of the interlinkage magnetic flux. The induced currents generated individually in the inductor pole coil 27 can be rectified by the diode 29 and then merged to flow individually in the electromagnet pole coils 28 connected in series. Can generate a large magnetic flux (electromagnetic force).
As a result, the synchronous reluctance motor 10 causes the exciting magnetic pole coil 27 and the electromagnetic pole coil 28 for the electromagnet to generate magnetic fluxes that interfere with each other and weaken each other when the exciting coil and the electromagnet are made common. Can be used effectively and smoothed, and can be efficiently recovered and output as energy.
Moreover, since the inductor pole coil 27 and the electromagnet pole coil 28 are arranged in multiple numbers in the circumferential direction of the rotor 21 and are multipolarized, the rotor is more effective than the case of the two-pole motor as described in Non-Patent Document 1 above. The amount of magnetic flux linked to one tooth of the teeth 22 can be dispersed in the circumferential direction, and the electromagnetic force (reluctance torque) acting on the individual rotor teeth 22 is also dispersed in the circumferential direction to suppress electromagnetic vibration. Can be silenced.

In addition, the inductor pole coil 27 and the electromagnet pole coil 28 are wound by using a wire made of a copper conductor, including the armature pole coil 14, and the electric conductivity is increased by using the copper conductor. By reducing the loss, an induced current can be efficiently generated and used as a field current. When a copper conductor is employed as the wire material of the coils 27, 28, and 14, it is preferable to employ a rectangular conductor, thereby reducing copper loss and heat loss due to coil resistance. Furthermore, as the form of the coils 27, 28, 14, the edge-wise coil is vertically wound so that the short side becomes the inner diameter side, thereby reducing the distributed capacitance (floating capacitance) and improving the frequency characteristics. In addition, since the perimeter of the wire is long, it is possible to suppress an increase in resistance due to the skin effect and a reduction in efficiency. As a result, the coils 27, 28, and 14 can recover more loss energy with a small amount of copper conductor. The wires of the coils 27, 28, and 14 are not limited to copper conductors, and may be selected for other purposes. For example, an aluminum bar conductor having a specific gravity of 1/3 of copper is used to reduce the weight. You may plan.
Furthermore, the armature pole coil 14 is formed in an open type status lot 13 having a flange-shaped portion 12b in which the inner peripheral surface 12a side of the stator teeth 12 is protruded in both the forward and reverse circumferential directions, thereby producing spatial harmonics. The magnetic flux is efficiently interlinked in the inductor pole coil 27.

As such a synchronous reluctance motor 10, for example, an inductor pole coil 27 is formed by making 18 turns of a flat copper wire of 2.0 × 1.0 mm to form 2.0 × 1.0 mm. The electromagnetic pole coil 28 is formed by winding nine turns of a rectangular copper wire. These numerical values are set in combination with the optimum numerical values that can be tolerated according to the outer diameter of the rotor 21, such as ensuring a space for winding the coil and a magnetic path width that does not cause magnetic saturation of the main magnetic path. For example, an example in which the outer diameter of the stator 11 is φ200 mm and the number of poles is 12 is shown.
In the synchronous reluctance motor 10, currents having current waveforms shown in FIGS. 6 to 8 flow through the inductor pole coils 27A and 27B and the electromagnet pole coils 28A and 28B shown in the simplified model of FIG.

Specifically, as shown in FIG. 6, the induced current generated in the inductor pole coil 27A is half-wave rectified by the diode 29A and supplied downstream. As shown in FIG. 7, the induced current generated in the inductor pole coil 27B is half-wave rectified by the diode 29B, inverted, and supplied downstream. Since the electromagnet pole coils 28A and 28B are connected in series, the combined waves shown in FIG. 8 obtained by synthesizing the induced currents shown in FIGS. 6 and 7 can be caused to flow as field currents to function as electromagnets. In short, the inductor pole coil 27 collects the spatial harmonics of the magnetic flux, which has conventionally been a cause of loss, by using the diodes 29A and 29B as an energy source, and the electromagnetic pole coil 28 effectively uses the recovered energy. A magnetic flux is generated, and the rotor 21 is efficiently rotated by adding the magnetic flux to the magnetic flux generated by the armature pole coil 14 of the stator 11.
Here, as shown in FIG. 6 and FIG. 7, the synchronous reluctance motor 10 has a field current generated by the inductor pole coil 27 and supplied to the electromagnet pole coil 28 pulsating three times during one electrical angle cycle. It can be seen that the main harmonic is the third harmonic, in which the inductor current is mainly generated in the inductor pole coil 27 is the third-order spatial harmonic magnetic flux.

As described above, in the synchronous reluctance motor 10, the rotor 21 rotates with reluctance torque generated by interlinking the magnetic flux generated by the armature pole coil 14 from the stator teeth 12 to the rotor teeth 22.
At this time, in the synchronous reluctance motor 10, as shown in FIG. 9, a field current supplied to the electromagnet pole coil 28 is generated by interlinking the spatial harmonic components of the magnetic flux with the inductor pole coil 27. Thus, it can be seen that the spatial harmonics that have conventionally been lost can be recovered as a field energy source, and that the reluctance torque increases as the field current increases.
FIG. 9 is a graph showing magnetic field analysis results performed with a sine wave current source that does not consider time harmonics, and it can be seen that the upper torque is linked to the amplitude of the lower field current. Some of the corresponding torque and field current amplitudes are connected by a broken line.
Therefore, in the synchronous reluctance motor 10, compared with a concentrated reluctance motor having a large pulsation due to fluctuations in magnetic resistance due to structural factors, the spatial harmonics that have conventionally been lost are recovered as a field energy source. It is possible to achieve a torque close to that of an IPM motor while reducing the amount of permanent magnet used, and to achieve high-quality rotation with reduced pulsation and torque ripple. The electromagnetic vibration of the stator 11 (k = 0 vibration mode for contraction / expansion) generated due to the above can be reduced, and the electromagnetic vibration and electromagnetic noise of the motor can be reduced.

  The synchronous reluctance motor 10 has a structure that mainly uses 3f-order spatial harmonic magnetic flux (f = 1, 2, 3,...), And has a number P of salient poles (rotor teeth 22) on the rotor 21 side. The number of status lots 13 on the stator 11 side is 2: 3. For example, the third-order spatial harmonic magnetic flux pulsates in a short cycle because the frequency is higher than the fundamental frequency input to the armature pole coil 14. For this reason, the rotor 21 generates an induced current efficiently by changing the magnetic flux intensity linked to the inductor pole coil 27 between the rotor teeth 22 and superimposes the spatial harmonic component superimposed on the fundamental frequency magnetic flux. Can be efficiently recovered and rotated.

As described above, the synchronous reluctance motor 10 has a structure that determines the quality of the relative magnetic action between the rotor 21 side and the stator 11 side, and includes the number of rotor teeth salient poles P and the number of status lots S. The reason why P / S = 2/3 is adopted as the ratio is to reduce the electromagnetic vibration and realize the rotation with small electromagnetic noise.
Specifically, when magnetic field analysis of the magnetic flux density distribution is performed, the magnetic flux density distribution is also distributed in the circumferential direction within a mechanical angle of 360 degrees according to the ratio of the number of salient teeth P and the number of status lots S. 11 is also unevenly distributed in the electromagnetic force distribution acting on the magnetic field 11.
In contrast, the synchronous reluctance motor 10 employs an 8P12S (P / S = 2/3) structure that combines the number of rotor teeth salient poles and the number of status lots of 12 to achieve a 360 ° mechanical angle all around. The magnetic fluxes having a uniform density distribution can be linked to each other, and the rotor 21 can be rotated in the stator 11 with high quality.
As a result, the synchronous reluctance motor 10 can be rotated without using the spatial harmonic magnetic flux as loss, efficiently recovering the lost energy, greatly reducing electromagnetic vibration, and improving quietness. Can be rotated.

As another aspect of the present embodiment, in the case of a radial gap structure such as the synchronous reluctance motor 10, it is often used to manufacture the stator 11 and the rotor 21 with a laminated structure of electromagnetic steel plates. For example, a soft magnetic composite powder (SoftMagnetic Composites) in which the surface of magnetic particles such as iron powder is subjected to insulation coating is further subjected to iron powder compression molding and heat treatment, so-called SMC core. It may be adopted.
Further, the radial gap structure is not limited to that of the synchronous reluctance motor 10, and an axial gap structure may be used. In this case, for example, the multi-gap structure shown in FIG. In this multi-gap type structure, an axial stator 31 facing the axial end surface side of the rotor 21 is formed on the stator 11 side, and an extended armature pole coil 14 'is wound around it. Further, on the rotor 21 side, a structure in which an inductor pole coil 47 facing the axial stator 31 on the axial end face side is wound around the core material 47a, and a permanent magnet (not shown) is provided between the core material 47a. Can be inserted.

In the case of producing a flat large-diameter motor structure, although not shown, a double gap motor structure in which a rotor is rotatably accommodated between an inner stator and an outer stator may be employed. In this double gap type motor structure, the inductor pole coil is arranged on the inner stator side to recover the lost energy, and the electromagnetic pole coil is arranged on the outer stator side to generate torque. Can be improved. In addition to the double gap type, in the single stator structure, the torque can be greatly improved by adopting a structure in which the electromagnetic pole coils are arranged in the radial gap direction and the inductor pole coils are arranged in the axial gap direction. .
Furthermore, the synchronous reluctance motor 10 is not limited to being mounted on a vehicle, and can be suitably employed as a drive source for wind power generation, machine tools, and the like.

  While embodiments of the invention have been disclosed, it will be apparent to those skilled in the art that changes may be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

DESCRIPTION OF SYMBOLS 10 Synchronous reluctance motor 11 Stator 12 Stator teeth 12a Inner peripheral surface 13 Status lot 14 Armature pole coil 21 Rotor 22 Rotor teeth 22a Outer peripheral surface 23 Rotor slots 27, 27A, 27B Inductor pole coils 27a, 28a Core materials 28, 28A , 28B Electromagnetic coil 29, 29A, 29B Diode 32A, 32B Bridge 32D Groove shape 32b, 34b Reinforcement bridge 32s Support slope 34 Support part 34s Support groove 35 Connection part 37A, 37B Permanent magnet

Claims (5)

A stator provided with an armature pole coil for inputting a plurality of phases of drive current, and a rotor provided with a plurality of salient poles for receiving a main rotational force by interlinking magnetic fluxes generated in the armature pole coil A synchronous reluctance motor comprising:
The rotor is
An inductor pole coil that is arranged on a magnetic path linked to the rotor side and that generates an induced current by the spatial harmonic component of the magnetic flux, the spatial harmonic component superimposed on the magnetic flux generated by the armature pole coil;
A rectifying element that rectifies the induced current generated in the inductor pole coil;
An electromagnetic pole coil that generates an electromagnetic force serving as an auxiliary rotational force for assisting the main rotational force by being energized and self-excited as a field current with the induced current rectified by the rectifying element;
A permanent magnet embedded to cooperate with the main rotational force by applying a magnetic force to the stator;
Synchronous reluctance motor comprising: The rotor is
A plurality of rotor teeth extending toward the inner peripheral surface of the stator and facing the outer peripheral surface to the inner peripheral surface;
The inductor pole coil is formed by wrapping around the rotor teeth,
The synchronous reluctance motor according to claim 1, wherein the permanent magnet is disposed in a rotor slot between the rotor teeth formed as a space around which the inductor pole coil is wound. The rotor is
An electromagnet core is formed around the electromagnet pole coil around the bottom of the rotor slot;
3. The synchronous reluctance motor according to claim 2, wherein the inductor pole coil is disposed on an outer peripheral side of the rotor and the electromagnetic pole coil is disposed on a rotating shaft side of the rotor. The electromagnetic pole coil is
It is installed so that the N poles and the S poles face each other across the rotor teeth,
The permanent magnet is
It is located on the outer peripheral surface side of the rotor in the rotor slot, and is installed so as to form a loop-shaped magnetic flux interlinking with a gap between the inner peripheral surface of the stator and a magnetic path. The synchronous reluctance motor according to claim 3. The rotor is
A support portion extending from the center of the bottom portion of the rotor slot toward the outer peripheral surface side of the rotor, and an outer peripheral surface side of the rotor teeth positioned on both sides of the rotor slot are respectively extended into the rotor slot. And first and second extensions,
The permanent magnet is
The first and second portions are arranged between each of the first and second extension portions and the support portion so that the magnetization direction opens in a V shape toward the outer peripheral surface of the rotor. Two permanent magnets,
A loop shape in which the N pole and the S pole are positioned on the outer peripheral surface side of the rotor on one end side of the first and second permanent magnets and the gap between the stator and the inner peripheral surface is linked as a magnetic path. The synchronous reluctance motor according to claim 4, wherein magnetic flux is formed.

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