JP2020088889A - Rotary electric machine - Google Patents

Abstract

To increase a torque generated by a field current by suppressing reduction of a field current magnetic flux.SOLUTION: A rotary electric machine comprises: a field yoke which is provided in an outer periphery of a stator core; and a first field coil and a second field coil which are provided at positions in the field yoke opposite to an axial end of a rotor core. A first region enclosed by magnets 18 is formed within a first face of rotor cores 14 and 16 of a rotor 10 opposite to the first field coil, and a second region enclosed by magnets 18 is formed within a second face of the rotor cores opposite to the second field coil. An additional rotor core 17 is provided in the first region and the second region, so that a field current magnetic flux is generated in the first region by current flowing to the first field coil and a field current magnetic flux is generated in the second region by current flowing to the second field coil.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rotary electric machine.

Patent Document 1 has a rotating shaft rotatably supported by a housing, a rotor attached to the rotating shaft, and a stator arranged on the outer periphery of the rotor and fixed to the housing, and the rotor is , A magnetically permeable member arranged in a cylindrical shape on the rotating shaft with a non-magnetic member sequentially interposed in the circumferential reinforcing member, and a non-magnetic material arranged on the outer periphery of the magnetically permeable member in the circumferential direction And a cylindrical magnetic path core made of a magnetically permeable material, and a magnet piece arranged in a cylindrical shape in which non-magnetic members are circumferentially spaced from each other and the interposed magnetic poles are alternately different. And a magnetically permeable member that extends at least to the outer peripheral surface of the permanent magnet member and that is axially stacked in the circumferential direction of the rotating shaft and that extends in the axial direction and both sides of the central laminated plate material. In addition, the electric motor/generator is described which is composed of side laminated plate materials sequentially laminated in the circumferential direction of the rotating shaft extending to the inner peripheral surface of the magnetic path core.

Patent Document 2 discloses a rotary shaft rotatably supported by a housing, a rotor attached to the rotary shaft, a stator arranged on the outer periphery corresponding to the rotor and fixed to the housing, and a rotor. A non-magnetic element having electromagnets respectively arranged on both ends of the rotary shaft, the rotor being disposed on the outer periphery of the rotary shaft and being circumferentially spaced so as to reach the electromagnet in the axial direction. Material, a cylindrical electromagnet core made of a magnetically permeable material, a cylindrical rotor yoke made of a magnetically permeable material arranged in a cylindrical shape on the electromagnet core, and a circumferentially spaced outer circumference of the rotor yoke. The permanent magnet member is composed of magnet pieces arranged in a cylindrical shape in which magnetic poles with non-magnetic members extending in the axial direction are alternately arranged, and the electromagnet has an end portion of the electromagnet core on the rotating shaft and A notch portion that is composed of a cylindrical electromagnet coil arranged in the magnetic path case of the housing corresponding to the end portion, and the electromagnet core is circumferentially separated so that magnetic flux flows in the axial direction and alternately in the opposite direction. Is described, which is formed by being spaced apart on the circumference.

Patent Document 3 discloses a rotor core in which a rotatable rotary shaft, a tubular stator core, a rotor core fixedly mounted on the rotary shaft, and a pair of magnetic poles of different magnetic properties are aligned in the radial direction of the rotor core. By setting a magnet set to, a field yoke provided on the outer periphery of the stator core, and a magnetic circuit between the field yoke and the rotor core, it is possible to control the magnetic flux density between the rotor core and the stator core. And a rotary electric motor with a wire.

JP-A-2000-261994 JP, 2000-354358, A JP, 2008-43099, A

In Patent Document 1, the N-pole side and the S-pole side of the rotor are magnetically separated by the air gap, and since the air gap exists in the magnetic circuit of the magnet magnetic flux, the magnetic resistance increases and the magnet magnetic flux decreases. I will end up. Further, since the core is arranged between the magnets on the rotor surface, the area (circumferential width) of the rotor core, which serves as the magnetic circuit of the field current magnetic flux, becomes smaller, the magnetic resistance increases, and the field current magnetic flux decreases. Will end up.

In Patent Document 2, the first rotor core is connected in an annular shape and the magnet is arranged on the surface, and the rotor core portion is not on the surface. Since the magnet is arranged in the magnetic circuit of the field current magnetic flux, the magnetic resistance is reduced. And the field current flux decreases. Further, since the field current magnetic flux flows through the annular rotor core on the back surface of the magnet, the magnetic resistance difference between the poles becomes small and the field current magnetic flux decreases.

In Patent Document 3, a so-called consequent pole configuration is used, and the field current magnetic flux flows in the opposite direction to the magnet magnetic flux on the magnet pole side, so that the armature interlinkage magnetic flux of the magnet pole side decreases. Further, although there are two field coils, the field current magnetic flux generated by each of them is concentrated on the salient pole portion, so that the salient pole side is magnetically saturated and the interlinkage magnetic flux is reduced.

It is an object of the present invention to provide a rotating electric machine capable of suppressing a decrease in field current magnetic flux and increasing torque due to a field current.

The present invention provides a rotatable shaft, a rotor core fixed to the shaft, a cylindrical stator core, a field yoke provided outside the stator core, and the rotor core of the field yoke. A first field coil and a second field coil, each of which is provided at a position facing an axial end of the rotor core and forms a magnetic circuit between the field yoke and the rotor core. A first region surrounded by a material having a relatively large magnetic resistance is formed in a first surface facing the first field coil, and a magnetic field is formed in a second surface of the rotor core facing the second field coil. A second region surrounded by a material having a relatively high resistance is formed, and the first region and the second region are magnetic poles different from each other, and an electric field flowing in the first field coil causes a field in the first region. A rotary electric machine in which a magnetic current magnetic flux is generated, and a field current magnetic flux is generated in the second region by a current flowing in the second field current coil.

In one embodiment of the present invention, a magnet provided in the rotor core so that different magnetic poles are alternately spaced apart in the circumferential direction, and the material having a relatively large magnetic resistance includes the magnet, The magnetic resistance in the axial direction between the field yoke and the first region in the first surface of the rotor core is such that the magnetic resistance in the first surface of the field yoke and the rotor core is relatively large. The magnetic reluctance in the axial direction between the field yoke and the second region in the second surface of the rotor core is smaller than the magnetic reluctance in the axial direction of the large material region. Is smaller than the axial magnetic resistance of the region of the material in which the magnetic resistance in the second surface is relatively large.

In another embodiment of the present invention, a first additional rotor core provided in the first region in the first surface of the rotor core and protruding in the direction of the first field coil, and the second surface of the rotor core. And a second additional rotor core that is provided in the second region inside and projects toward the second field coil.

In still another embodiment of the present invention, the rotor core includes a cylindrical first rotor core and a second rotor core provided on an inner peripheral side of the first rotor core, and the magnet is the first rotor core. It is provided in at least one of the second rotor cores.

In still another embodiment of the present invention, the rotor core includes a tubular first rotor core and a second rotor core provided on an inner peripheral side of the first rotor core, and the first additional rotor core is the first rotor core. It is provided in at least one of the first rotor core and the second rotor core, and the second additional rotor core is provided in at least one of the first rotor core and the second rotor core.

In still another embodiment of the present invention, the first additional rotor core and the second additional rotor core are provided so as to be separated from each other in the circumferential direction.

In still another embodiment of the present invention, the first additional rotor core and the second additional rotor core are provided so as to be coupled in the circumferential direction.

In yet another embodiment of the present invention, the magnet extends parallel to the axial direction.

In still another embodiment of the present invention, the magnet extends obliquely in the axial direction.

In still another embodiment of the present invention, in the rotor core, the inner diameter side of the end portion on the axially opposite side to the side on which the first additional rotor coil is provided is partially deleted, and 2 The inner diameter side of the end portion on the axially opposite side to the side on which the additional rotor coil is provided is partially deleted.

In still another embodiment of the present invention, the first rotor core and the second rotor core are radially coupled and circumferentially coupled.

According to the present invention, the field current magnetic flux is generated in the first region where the magnetic resistance is relatively small by the current flowing through the first field coil, and the magnetic resistance is relatively generated by the current flowing through the second field current coil. Since the field current magnetic flux is generated in the small second region, it is possible to suppress the decrease of the field current magnetic flux and increase the torque due to the field current.

It is a perspective view of the rotor of an embodiment. It is a partially expanded view of FIG. It is a top view of the rotary electric machine of embodiment. It is an armature interlinkage magnetic flux explanatory drawing of the rotary electric machine of embodiment. It is a magnet magnetic flux explanatory drawing of the rotary electric machine of embodiment. It is a field current magnetic flux explanatory drawing of the rotary electric machine of embodiment. 6 is a graph showing the relationship between the field current and the flux linkage in Patent Document 1. FIG. 6 is a graph showing the relationship between the field current and the flux linkage in Patent Document 2. FIG. It is a graph figure which shows the relationship between the field current and linkage flux of embodiment. It is a graph figure which shows the relationship of a field current and an interlinkage magnetic flux of patent document 3 and embodiment. It is a magnet placement explanatory view of an embodiment. It is another magnet arrangement explanatory drawing of embodiment. It is explanatory drawing of another magnet arrangement of embodiment. It is explanatory drawing of another magnet arrangement of embodiment. FIG. 6 is an explanatory diagram of another additional rotor core arrangement of the embodiment. It is an explanatory view of arrangement of another additional rotor core of an embodiment. It is a connection explanatory view (the 1) of the 1st rotor core and the 2nd rotor core of an embodiment. It is a connection explanatory view (the 2) of the 1st rotor core and the 2nd rotor core of an embodiment. It is explanatory drawing of another magnet arrangement of embodiment. It is a perspective view of the rotary electric machine of an embodiment. It is a perspective view of another rotary electric machine of an embodiment. It is an additional rotor core arrangement explanatory drawing (the 1) of an embodiment. It is an additional rotor core arrangement explanatory drawing (the 2) of embodiment. It is another additional rotor core arrangement explanatory drawing (the 1) of an embodiment. It is other additional rotor core arrangement|positioning explanatory drawing (2) of embodiment. It is explanatory drawing of another magnet arrangement of embodiment. It is explanatory drawing of another magnet arrangement of embodiment. It is another rotor core shape explanatory drawing of embodiment.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a perspective view of a rotor 10 of a rotary electric machine according to this embodiment. Further, FIG. 2 is a partially enlarged view of the rotor 10 shown in FIG. 1, and more specifically, is a perspective view of a quarter cut except the shaft 12 of the rotor 10.

Here, the stator arranged on the outer peripheral side of the rotor 10 with a gap formed between the rotor 10 and the rotor 10 has the same configuration as, for example, Patent Documents 1 and 2. Specifically, the stator includes a stator core, a plurality of stator teeth formed on the inner surface of the stator core and protruding in the radial direction of the stator core, and a stator coil wound around the stator teeth. The stator teeth are formed at equal intervals in the circumferential direction. The stator coil constitutes a U-phase coil, a V-phase coil, and a W-phase coil, and one end of the stator coil serves as a terminal and the other end serves as a neutral point. Any one of a U-phase cable, a V-phase cable and a W-phase cable of the inverter three-phase cable is connected to the terminal, and the neutral point is commonly connected to one point. A control current according to the torque command value is supplied from the control device to the three-phase cable.

A field yoke and a field coil are provided outside the stator. The field yoke is formed on the top plate portion disposed at a position axially separated from both ends of the stator and the rotor 10, a cylindrical side wall portion formed on the peripheral portion of the top plate portion, and the top plate portion. And a cylindrical protruding portion. A through hole is formed in the center of the top plate portion, and the shaft 12 is inserted into the through hole. Further, the side wall portion is fixed to the outer surface of the stator core. The cylindrical protrusion formed on the top plate is formed on the inner surface of the top plate and protrudes toward the axial end of the rotor 10. Between the protrusion and the end of the rotor 10, the protrusion and the end of the rotor 10 are close to each other so that the lines of magnetic force are not interrupted.

The field coil is wound around the outer surface of the protrusion. By supplying a field current to the field coil, it is possible to induce, for example, the magnetism of the S pole on the end side of the protrusion and the magnetism of the N pole on the side wall. Specifically, by passing a field current through the field coil, it passes through the top plate portion of the field yoke, enters the stator core from the side wall portion, enters the rotor core of the rotor 10 through the gap, and moves inside the rotor core. A magnetic circuit is formed that advances in the axial direction and enters the field yoke from the axial end of the rotor core via the projection. The field coils are arranged at positions facing both axial ends of the rotor 10, respectively. The configurations of the field yoke and the field coil will be described later.

1 and 2, the rotor 10 includes a rotor core cylindrically arranged on the outer circumference of a shaft 12 as a rotating shaft, and magnets 18n and 18s sequentially arranged on the outer circumference side of the rotor core so that their magnetic poles are different from each other. including. The magnets 18n and 18s are arranged in a spoke shape with being spaced apart in the circumferential direction, and are arranged so as to extend in the axial direction of the rotor 10 (axial direction of the shaft 12).

The rotor core includes a cylindrical first rotor core 14 on the outer peripheral side and a second rotor core 16 on the inner peripheral side. The first rotor core 14 is circumferentially divided into the first rotor core 14n and the first rotor core 14s by the magnets 18n and 18s. Between the outer circumference of the shaft 12 and the magnets 18n, 18s, a non-magnetic body 20 (or a gap) extending in the radial direction from the outer circumference of the shaft 12 to the magnets 18n, 18s is arranged. The second rotor core 16 is circumferentially divided into the second rotor core 16n and the second rotor core 16s by the nonmagnetic material 20 (or the air gap). Here, n and s attached to the symbols mean the north pole and the south pole of the magnetic poles, respectively.

FIG. 3 shows a top view of a quarter cut of the rotor 10. A stator coil (armature winding) 6 is wound around the yoke portion of the stator core 5 of the stator to form an N pole (first pole) and an S pole (second pole). On the other hand, magnets 18n and 18s are alternately arranged in the circumferential direction of the rotor 10, and the first rotor core 14 and the second rotor core 16 are magnetically separated by the magnets 18n and 18s and the non-magnetic body 20 into the N pole and the S pole, respectively. To be done. Regarding the magnetic resistance, the region where the magnets 18n and 18s and the non-magnetic body 20 are arranged is a region where the magnetic resistance is relatively large, and the region where the magnets 18n and 18s and the non-magnetic body 20 are not arranged, in other words, The regions of the first rotor cores 14n and 14s and the second rotor cores 16n and 16s surrounded by the magnets 18n and 18s and the non-magnetic material 20 are regions where the magnetic resistance is relatively small.

FIG. 4 is a top view of a quarter cut of the rotor 10, and the arrow 100 indicates the direction of the armature flux linkage that links the stator coil 6 of the stator. Further, FIG. 5 is a top view of a quarter cut of the rotor 10, and a magnet flux generated by the magnets 18n and 18s is indicated by a broken line 200.

In Patent Document 1, since there is a gap in the magnetic circuit of the magnetic flux of the magnet, the magnetic resistance increases and the magnetic flux of the magnet decreases, but in the present embodiment, the magnetic circuit of the magnetic flux 200 of the magnet has a magnetic flux of 200 as shown in FIG. Since there is no air gap between the magnet 18s and the first rotor core 14n and between the magnet 18s and the first rotor core 14s, the magnetic resistance does not increase and the magnet magnetic flux does not decrease.

Returning to FIG. 1 and FIG. 2 again, the first rotor cores 14n, 14s and the second rotor cores 16n, 16s have N poles and S poles alternately arranged in the circumferential direction, but regarding the second rotor cores 16n, 16s, The additional second rotor cores 17, that is, the additional second rotor cores 17n and 17s are alternately added in the direction and are extended in the axial direction.

That is, for the second rotor core 16s, the additional second rotor core 17s is added in the axially upward direction in the drawing to extend in the axially upward direction, and for the second rotor core 16n, the additional second rotor core 17s is added in the axial downward direction in the drawing. Two rotor cores 17n are added and extended downward in the axial direction. Of the two end surfaces of the rotor 10, the end surface located in the axial upper direction in the drawing is the first surface, and the end surface located in the axial lower direction in the drawing is the second surface. The first surface is arranged in the circumferential direction. The additional second rotor core 17s is added only to the second rotor core 16s, and the additional second rotor core 17 is not added to the second rotor core 16n. Further, on the second surface, the additional second rotor core 17n is added only to the second rotor cores 16n arranged in the circumferential direction, and the additional second rotor core 17 is not added to the second rotor core 16s. Therefore, on the first surface, the unevenness is alternately formed in the circumferential direction due to the addition of the additional rotor core 17s, and also on the second surface, the unevenness is alternately formed in the circumferential direction due to the addition of the additional rotor core 17n. . Since the convex portion of the first surface is a portion corresponding to the second rotor core 16s and the convex portion of the second surface is a portion corresponding to the second rotor core 16n, the unevenness of the first surface and the unevenness of the second surface are It shifts in the circumferential direction (the convex portion of the first surface corresponds to the concave portion of the second surface, and the convex portion of the first surface corresponds to the concave portion of the second surface).

As described above, the field coil wound around the protrusion of the field yoke faces the first surface and the second surface of the rotor 10, respectively. If the first field coil and the field coil facing the second surface are the second field coils, the additional second rotor core 17s on the first surface extends toward the first field coil and the additional second surface is added. The second rotor core 17n extends toward the second field coil. Therefore, in the relationship between the first field coil and the second rotor cores 16n and 16s on the first surface, the axial direction between the first field coil and the second rotor core 16s is increased by the amount of the additional second rotor core 17s added. The magnetic resistance is reduced, and the magnetic flux generated in the first field coil selectively flows through the second rotor core 16s (and the first rotor core 14s). When the regions of the first rotor core 14s, the second rotor core 16s, and the additional rotor core 17s on the first surface are defined as the first region, the first region is a region having a relatively small magnetic resistance, and the magnetic flux generated in the first field coil. Flows through the first region having a relatively small magnetic resistance without flowing through the magnets 18n and 18s having a relatively large magnetic resistance. The additional second rotor core 17s may form the first region.

Further, in the relationship between the second field coil and the second rotor cores 16n and 16s on the second surface, the axial direction between the second field coil and the second rotor core 16n is increased by the additional second rotor core 17n. The magnetic resistance decreases, and the magnetic flux generated in the second field coil selectively flows through the second rotor core 16n (and the first rotor core 14n). When the regions of the first rotor core 14n, the second rotor core 16n, and the additional rotor core 17n on the second surface are defined as the second region, the second region is a region having a relatively small magnetic resistance, and the magnetic flux generated in the second field coil is generated. Flows through the second region having a relatively small magnetic resistance without flowing through the magnets 18n and 18s having a relatively large magnetic resistance. The second region may be formed by the additional second rotor core 17n.

Therefore, different magnetic poles are alternately formed in the first rotor core 14n and the first rotor core 14s by the magnetic flux generated in each of the first field coil and the second field coil.

FIG. 6 is a top view of a quarter cut of the rotor 10, and the broken line 300 indicates the field current magnetic flux generated by the first field coil and the second field coil. On the first surface, the additional second rotor core 17s selectively causes the magnetic flux generated in the first field coil to flow to the first rotor core 14s, and on the second surface, the additional second rotor core 17n causes the magnetic flux generated in the second field coil to flow. Since it selectively flows through the first rotor core 14n, field current magnetic fluxes having different directions alternately in the circumferential direction are generated. When comparing the magnet magnetic flux 200 of FIG. 5 and the field current magnetic flux 300 of FIG. 6, the magnet magnetic flux 200 flowing in the first rotor core 14n and the field current magnetic flux 300 are in the same direction, and the magnet flowing in the first rotor core 14s. The magnetic flux 200 and the field current magnetic flux 300 have the same direction. This means strengthening the magnet flux by the field current flux.

In FIG. 6, the width in the circumferential direction of the first rotor cores 14n and 14s, which is the magnetic circuit of the field current magnetic flux 300, is smaller than that in the case of Patent Document 1 because there is no air gap in the circumferential direction of the first rotor cores 14n and 14s. Wide enough.

Further, since the magnets 18n and 18s having relatively large magnetic resistance do not exist in the magnetic circuit of the field current magnetic flux 300, the magnetic resistance does not increase by the amount of the magnets as in Patent Document 2.

Further, since the field current magnetic flux 300 is a magnetic circuit that is not concentrated on one pole, the field current magnetic flux generated by the two field coils is concentrated on the iron salient pole portion and the salient pole side is generated as in Patent Document 3. The magnetic flux is not magnetically saturated, and the decrease in the interlinkage magnetic flux is suppressed.

That is, in the rotor 10 of the present embodiment, since there is no gap in the magnetic circuit of the magnet magnetic flux and the magnetic resistance does not increase, the magnet magnetic flux can be effectively used. Further, since the magnet does not exist in the magnetic circuit of the field current magnetic flux and is not concentrated on one pole, the field current magnetic flux can be effectively used.

7, FIG. 8 and FIG. 9 show interlinkage magnetic fluxes of Patent Document 1, Patent Document 2 and this embodiment, respectively. The horizontal axis represents the field current and the vertical axis represents the flux linkage amount, which is the result of calculation of the flux linkage amount when the field current is changed by magnetic field analysis. The interlinkage magnetic flux is shown separately for the magnet magnetic flux and the field current magnetic flux. In these drawings, the structure of the stator is the same. When the field current flowing through the first field coil and the second field coil is 0, it is the case of only the magnet magnetic flux, and the value of the interlinkage magnetic flux at that time is the magnet magnetic flux.

FIG. 7 shows the interlinkage magnetic flux of Patent Document 1, and the magnet magnetic flux is relatively small because of the existence of the air gap in the magnetic circuit of the magnet magnetic flux.

FIG. 8 shows the interlinking magnetic flux of Patent Document 2, and although the magnet magnetic flux is relatively large, the field current magnetic flux is relatively small because a magnet having a large magnetic resistance exists in the magnetic circuit of the field current magnetic flux. ing.

FIG. 9 shows the interlinkage magnetic flux of this embodiment, and shows good values for both the magnet magnetic flux and the field current magnetic flux. This is because, as already described, there is no air gap in the magnetic circuit of the magnetic flux of the magnet, and no magnet is present in the magnetic circuit of the field current magnetic flux.

FIG. 10 shows the interlinkage magnetic flux of Patent Document 3 and this embodiment. In the figure, the broken line is the flux linkage of Patent Document 3, and the solid line is the flux linkage of this embodiment. It should be noted that although the stator structure is the same and the rotor structure is different between Patent Documents 1 and 2, the stator structure and the rotor structure are different between Patent Document 3 and this embodiment, and therefore the increase from the magnet magnetic flux is increased. That is, only the field current magnetic flux is shown as the interlinkage magnetic flux. In Patent Document 3, since the field current magnetic flux concentrates on the salient pole portion, it is magnetically saturated and reaches a peak, whereas in the present embodiment, since it is not magnetically saturated, the field current magnetic flux increases as the field current increases. I understand that

As described above, in the rotary electric machine according to the present embodiment, both the magnetic flux of the magnet and the magnetic flux of the field current can be increased as compared with the conventional rotary electric machine, and the torque of the magnet and the torque of the field current can both be increased. ..

Although the spoke-shaped magnets 18 are arranged between the first rotor cores 14 in this embodiment, other arrangement configurations may be used.

FIG. 11 shows the arrangement configuration of the magnets 18 according to the present embodiment, and is the arrangement between the first rotor cores 14 on the outer peripheral side of the rotor cores as described above. The magnet 18 and the shaft 12 are magnetically separated from each other by a non-magnetic material 20 (or a gap) extending in the radial direction.

FIG. 12 shows another arrangement configuration of the magnet 18, which is arranged between the second rotor cores 16 on the inner peripheral side of the rotor core. A space between the magnet 18 and the outer circumference of the rotor core is magnetically separated by a non-magnetic body 20 (or a gap) extending in the radial direction.

FIG. 13 shows still another arrangement configuration of the magnets 18, which is disposed between the first rotor cores 14 and between the second rotor cores 16.

FIG. 14 shows still another arrangement configuration of the magnets 18, which is arranged between the first rotor cores 14 and a portion thereof extends between the second rotor cores 16 similarly to FIG. 11. It can be said to be an intermediate configuration between FIG. 11 and FIG.

Although any of the arrangement configurations shown in FIGS. 11 to 14 is possible, it is more desirable that the magnet 18 is closer to the stator side. This is because the amount of magnetic flux of the armature increases closer to the stator side, and the torque generated by the magnet increases.

Further, in order to reduce the loss due to the eddy current on the surface of the gap between the rotor 10 and the stator in the present embodiment, it is desirable that the first rotor core 14 be made of a laminated steel plate or the like. That is, the magnetic resistance of the first rotor core 14 in the circumferential direction and the radial direction is smaller than that in the axial direction. Since the field current magnetic flux flows from the axial direction of the second rotor core 16 through the additional second rotor cores 17n and 17s, the magnetic reluctance in the axial direction of the second rotor core 16 is the magnetic field in the axial direction of the first rotor core 14. It is desirable to be smaller than the resistance.

In the present embodiment, the additional second rotor cores 17n, 17s are added in the axial direction of the second rotor cores 16n, 16s, but not necessarily in the axial direction of the second rotor cores 16n, 16s, but the axes of the first rotor cores 14n, 14s. A rotor core may be added in the direction or in the axial direction of the first rotor cores 14n and 14s and the second rotor cores 16n and 16s. It can be said that the additional first rotor core is added when the first rotor cores 14n and 14s are added in the axial direction. I can say. Hereinafter, the additional first rotor core and the additional second rotor core are collectively referred to as an additional rotor core.

FIG. 15 shows an arrangement configuration in which the additional rotor core 17 is added in the axial direction of the first rotor cores 14n and 14s. Although the drawing shows the case where the additional rotor core 17s is added to the first surface, the additional rotor core 17n is added to the second surface.

FIG. 16 shows an arrangement configuration in which the additional rotor core 17 is added in the axial direction of the first rotor cores 14n and 14s and the second rotor cores 16n and 16s.

Although either of the arrangement configurations of FIG. 15 and FIG. 16 is possible, when the first rotor core 14 is made of laminated steel plates, the magnetic resistance in the axial direction becomes large, and the field current magnetic flux is generated by the first rotor core 14 and the second rotor core 14. Since the rotor core 16 flows in the axial direction, it is more desirable to add the additional rotor core 17 only in the axial direction of the second rotor core 16 from the viewpoint of magnetic resistance.

Further, in the present embodiment, the shaft 12 is preferably made of a material having a large magnetic resistance such as a non-magnetic material. Alternatively, it is desirable to dispose a material having a large magnetic resistance, such as an air gap or a non-magnetic material, between the shaft 12 and the second rotor core 16. The reason is that when the second rotor core 16 and the shaft 12 are magnetically coupled, not only the magnet magnetic flux short-circuits the inside of the shaft 12 to reduce the magnet magnetic flux, but also the field current magnetic flux flows in the shaft 12. This is because the field current torque also decreases.

Further, it is desirable that the first rotor core 14 and the second rotor core 16 are coupled not only in the radial direction but also in the circumferential direction. By mechanically connecting the first rotor core 14 and the second rotor core 16 in the circumferential direction, the mechanical strength of the first rotor core 14 and the second rotor core 16 can be improved.

17 and 18 show the structure of the rotor 10 in this case. As shown in FIG. 18, bridge portions 22 and 23 are formed at both ends of the magnet 18s in the radial direction. The first rotor cores 14n and 14s forming the first rotor core 14 are circumferentially connected by the bridge portion 22. In addition, the second rotor cores 16n and 16s forming the second rotor core 16 are circumferentially connected by a bridge portion 23 provided between the second rotor cores 16n and 16s and the shaft 12 (not shown).

Even in this case, when focusing on the first rotor core 14n and the second rotor core 16n, for example, it can be said that the region is surrounded by the magnets 18n and 18s having a relatively large magnetic resistance and the non-magnetic body 20.

In addition, in the present embodiment, the configuration in which the additional rotor core is added in the axial direction on the premise of the magnets 18 arranged in the spoke shape is illustrated, but the arrangement of the magnets 18 is not limited to the spoke shape, and other arrangements are possible. is there.

FIG. 19 shows a configuration in which the magnets 18 are arranged in a V shape. The rotor 10 includes a magnet pair 18s formed of two magnets arranged in a V shape, and two magnets arranged in a V shape and spaced apart from the magnet pair 18s in the circumferential direction. A magnet pair 18n is provided. The pair of magnets 18n and 18s have an IPM (Interior Permanent Magnet) configuration that is inserted into the magnet insertion hole formed in the rotor 10. The additional rotor core 17s is added to the area surrounded by the magnet pair 18s arranged in a V shape. Also in this case, the additional rotor core 17s is added to a region surrounded by a region having a relatively large magnetic resistance in the rotor surface.
Further, the additional rotor core 17n is added to the area surrounded by the pair of magnets 18n arranged in a V shape on the axially lower surface.

In FIG. 19, an additional rotor core 17 is added in the axial direction in a region surrounded by a region having a relatively large magnetic resistance in the rotor surface, and the axial magnetic resistance difference is used. In addition to the difference, the magnetic resistance difference in the radial direction may be used.

FIG. 20 shows the configuration of the rotating electric machine of this embodiment that utilizes the magnetic resistance difference in the axial direction. The structure of the rotor 10 is as shown in FIG. 1, but FIG. 20 also shows the arrangement of the field yoke and field coil of the stator. With reference to FIG. 20, the positional relationship between the rotor 10 and the field yoke and the two field coils in this embodiment can be more clearly understood.

As described above, the field yoke 30 and the two field coils 40 and 50 are provided outside the stator. The field yoke 30 includes a top plate portion 30a arranged at a position axially separated from both ends of the rotor 10, a cylindrical side wall portion 30b formed on a peripheral portion of the top plate portion 30a, and a top plate portion. It has a cylindrical protrusion 30c formed on 30a. A through hole is formed in the center of the top plate portion 30a, and the shaft 12 is inserted into this through hole. The side wall portion 30b is fixed to the outer surface of the stator core. The cylindrical protrusion 30c formed on the top plate portion 30a is formed on the inner surface of the top plate portion 30a and projects toward the axial end portion of the rotor 10.

The field coil 40 is wound around the outer surface of the protrusion 30c in the axially upward direction in the figure. Further, the field coil 50 is wound around the outer surface of the protrusion 30c on the axial lower side in the drawing. A field current magnetic flux is generated by passing a field current in the same direction through the field coils 40 and 50. By passing a field current through the field coil 40, the field coil 30 passes through the top plate portion 30a, enters into the stator core from the side wall portion 30b, and the first rotor core 14 and the second rotor core 16 of the rotor 10 through the gap. Into the inside of the second rotor core 16 and the additional rotor core (additional second rotor core) 17 in the axial direction, and extends from the axial end of the additional rotor core (additional second rotor core) 17 via the projection 30c to the field yoke 30. The magnetic circuit 400 is formed so as to enter.

FIG. 21 shows the configuration of a rotating electric machine according to another embodiment that utilizes the magnetic resistance difference in the radial direction. As in the case of FIG. 20, the additional second rotor core 17 is added to the second rotor core 16 in the axial direction. The additional second rotor core 17 is further extended in the axial direction as compared with FIG. 20, and the top plate of the field yoke 30. It reaches near the portion 30a. Therefore, due to the additional second rotor core 17 extending further in the axial direction, a magnetic resistance difference is generated in the radial direction in the top plate portion 30a of the field yoke 30, and another portion is added to the portion where the additional second rotor core 17 is added. The magnetic resistance is smaller than that of. That is, by adding the additional second rotor core 17, a magnetic resistance difference is generated not only in the axial direction but also in the radial direction, and the magnetic flux generated by the field coil 40 selectively flows through the additional second rotor core 17. The magnetic flux generated by the field coil 50 also selectively flows through the additional second rotor core 17 in the same manner.

Also in the configuration of FIG. 21, the magnet 18 is not arranged in the magnetic circuit 400 formed by the field coil 40, so that the reduction of the field current magnetic flux by the magnet 18 is prevented. The same applies to the magnetic circuit 400 formed by the field coil 50.

Further, in the present embodiment, as in the perspective view of FIG. 22A and the perspective view of the additional rotor core 17 shown in FIG. 22B, the additional rotor cores 17 are arranged so as to be separated from each other in the circumferential direction, but the magnetic resistance difference is different. It may be connected to each other in the circumferential direction as long as it can be secured.

23A and 23B show the configuration of the additional rotor core 17 in this case. The additional rotor cores 17 are arranged so as to be spaced apart from each other in the circumferential direction, and their axial ends, that is, the ends of the field yoke 30 on the side of the protrusion 30c are circumferentially coupled by the annular core 19s. .. As a result, the mechanical strength of the additional rotor core 17 can be improved while maintaining the magnetic resistance difference.

Further, in the present embodiment, the magnets 18 are arranged in a spoke shape and extend in the axial direction, but the magnets 18 may be arranged at a certain angle instead of being parallel to the axial direction. In this case, the first rotor core 14 and the second rotor core 16 may also be arranged to be inclined with respect to the axial direction by the inclined arrangement of the magnets 18.

24 and 25 show a configuration in which the magnet 18 is arranged so as to be inclined with respect to the axial direction. 24 and 25, the inclination angle of the magnet 18 is different. With these configurations, the same effect as that of FIG. 1 and the like can be obtained. By arranging the first rotor core 14 and the second rotor core 16 together with the magnets 18 in an inclined manner, the area of the surface of the additional second rotor core 17 through which the field current magnetic flux passes increases, so that the magnetic saturation is reduced accordingly. The field current torque can be further increased.

Further, in the present embodiment, in the second rotor core 16, the end on the side opposite to the side to which the additional rotor core 17 is added in the axial direction may be partially removed (cut) in the radial direction.

FIG. 26 shows the structure of the rotor 10 in this case. The additional second rotor core 17 is added in the axial direction of the second rotor core 16, and a part of the second rotor core 16 on the axially opposite side is partially cut in the radial direction. In the figure, a partially cut surface 16a is shown. As shown in the magnetic circuit 400 of FIG. 20, when a field current is passed through the field coil 40, it passes through the top plate portion 30a of the field yoke 30 and enters into the stator core from the side wall portion 30b and the rotor through the gap. The first rotor core 14 and the second rotor core 16 of FIG. 10 enter the second rotor core 16 and the additional rotor core 17 in the axial direction, and from the axial end of the additional rotor core 17 to the field yoke 30 via the protrusion 30c. Since the magnetic circuit 400 is formed so as to enter, the field current magnetic flux does not pass or can be ignored on the inner diameter side of the end of the second rotor core 16 on the opposite side to which the additional rotor core 17 is not added. It is a very small amount. Therefore, even if this part is partially cut, the magnetic flux amount of the field current magnetic flux hardly changes, and the weight of the second rotor core 16 can be reduced. Since a space is generated in the part that is partially cut, the space can be used for other purposes.

10 rotor, 12 shaft, 14, 14n, 14s first rotor core, 16, 16n, 16s second rotor core, 17, 17n, 17s additional rotor core (additional second rotor core), 18, 18n, 18s magnet, 20 non-magnetic material, 22, 23 Bridge part, 30 Field yoke, 30a Top plate part, 30b Side wall part, 30c Projection part, 40, 50 Field coil.

Claims (11)

With a rotatable shaft,
A rotor core fixed to the shaft;
A stator core formed in a tubular shape,
A field yoke provided outside the stator core,
A first field coil and a second field coil which are respectively provided at positions of the field yoke facing the axial end of the rotor core and which form a magnetic circuit between the field yoke and the rotor core; ,
Equipped with
A first region surrounded by a material having a relatively large magnetic resistance is formed in a first surface of the rotor core facing the first field coil, and a second region facing the second field coil of the rotor core is formed. A second region surrounded by a material having a relatively large magnetic resistance is formed in the surface, and the first region and the second region are magnetic poles different from each other,
A rotary electric machine in which a field current magnetic flux is generated in the first region by the current flowing in the first field coil and a field current magnetic flux is generated in the second region by the current flowing in the second field current coil. Magnets provided on the rotor core so that different magnetic poles are alternately spaced apart in the circumferential direction,
Equipped with
The material having a relatively high magnetic resistance includes the magnet,
The magnetic resistance in the axial direction between the field yoke and the first region in the first surface of the rotor core is such that the magnetic resistance in the first surface of the field yoke and the rotor core is relatively large. The magnetic reluctance in the axial direction between the field yoke and the second region in the second surface of the rotor core is smaller than the magnetic reluctance in the axial direction of the large material region. The rotary electric machine according to claim 1, wherein the magnetic resistance in the second surface is smaller than an axial magnetic resistance of a region of a material having a relatively large magnetic resistance. A first additional rotor core that is provided in the first region within the first surface of the rotor core and that projects toward the first field coil;
A second additional rotor core that is provided in the second region within the second surface of the rotor core and that projects toward the second field coil;
The rotary electric machine according to claim 2, further comprising: The rotor core is
A tubular first rotor core;
A second rotor core provided on the inner peripheral side of the first rotor core;
Equipped with
The rotating electric machine according to claim 2, wherein the magnet is provided in at least one of the first rotor core and the second rotor core. The rotor core is
A tubular first rotor core;
A second rotor core provided on the inner peripheral side of the first rotor core;
Equipped with
The first additional rotor core is provided in at least one of the first rotor core and the second rotor core,
The rotary electric machine according to claim 3, wherein the second additional rotor core is provided in at least one of the first rotor core and the second rotor core. The rotating electrical machine according to claim 3, wherein the first additional rotor core and the second additional rotor core are provided so as to be separated from each other in the circumferential direction. The rotating electrical machine according to claim 3, wherein the first additional rotor core and the second additional rotor core are provided so as to be coupled in the circumferential direction. The rotating electric machine according to claim 2, wherein the magnet extends parallel to the axial direction. The rotating electric machine according to claim 2, wherein the magnet extends obliquely in the axial direction. Of the rotor core, the inner diameter side of the end portion axially opposite to the side on which the first additional rotor coil is provided is partially deleted,
The rotary electric machine according to claim 3, wherein an inner diameter side of an end of the rotor core, which is axially opposite to a side on which the second additional rotor coil is provided, is partially removed. The rotary electric machine according to claim 4, wherein the first rotor core and the second rotor core are radially coupled and circumferentially coupled.

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