JP5685847B2 - Electric motor system - Google Patents

Description

  The present invention relates to an electric motor system.

  Patent Document 1 discloses a rotating electrical machine that includes a stator having a salient pole portion (tooth) and a slot, and a coil is wound around the salient pole portion via an insulator.

JP 2009-130958 A

  However, in the case where the coil is wound around the salient pole portion like the conventional rotating electric machine described above, it is necessary to move the coil back and forth between adjacent slots, and the coil is wound around the upper end surface and the lower end surface in the axial direction of the salient pole portion. Coil (hereinafter referred to as “end coil”). The end coil does not contribute to generating a rotating magnetic field necessary for rotating the rotor in the stator, and becomes a source of leakage magnetic field. Therefore, even if various electric parts such as inverters are arranged near the end of the salient pole in the axial direction, noise and eddy current loss occur due to the leakage magnetic field, and the electric motor system including the rotating electric machine and the inverter However, there was a problem of increasing the size.

  The present invention has been made paying attention to such problems, and aims to reduce the size of an electric motor system.

  The present invention relates to a stator having an annular back yoke portion and a plurality of salient pole portions protruding from an inner peripheral surface of the back yoke portion, and a rotor whose outer periphery is covered by the stator and rotated by a rotating magnetic field generated in the stator. And a conductor rod inserted between the salient pole portions, and the direction of the current flowing through the conductor rod is alternately switched by a semiconductor element provided at the end of the conductor rod in the rotor rotation axis direction, and a rotating magnetic field is generated in the stator. This is an electric motor system.

  According to the present invention, since the conductor rod is inserted between the salient pole parts instead of winding the coil around the salient pole parts, the leakage magnetic field generating source is disposed at the end of the salient pole part in the rotor rotation axis direction. There is no end coil. Therefore, electrical parts such as semiconductor elements can be provided in the vicinity of the rotor rotation axis direction end portion of the stator, and the motor system can be miniaturized.

It is a figure which shows the stator by 1st Embodiment of this invention. It is a figure which shows the electric circuit comprised by the conductor rod and power module by 1st Embodiment of this invention. It is sectional drawing of the rotary electric machine by 1st Embodiment of this invention. It is a schematic block diagram of the electric vehicle carrying the rotary electric machine by 1st Embodiment of this invention. It is a figure which shows the stator by 2nd Embodiment of this invention. It is a figure which shows the electric circuit comprised with the conductor rod and power module by 2nd Embodiment of this invention. It is a schematic block diagram of the electric vehicle carrying the rotary electric machine by 2nd Embodiment of this invention. It is a figure explaining the conductor rod and its manufacturing method by 3rd Embodiment of this invention. It is a perspective view of the conductor bar by a 4th embodiment of the present invention. It is a perspective view of the conductor bar which provided the power module in the both ends by 4th Embodiment of this invention. It is sectional drawing of the rotary electric machine by 5th Embodiment of this invention. It is a schematic block diagram of the electric vehicle carrying the rotary electric machine by a prior art example.

  Hereinafter, each embodiment of the present invention will be described with reference to the drawings. In the following description, “axial direction” refers to the axial direction of the rotating shaft 6 of the rotating electrical machine 10.

(First embodiment)
FIG. 1 is a diagram illustrating a stator 1 according to the present embodiment. FIG. 1A is a perspective view showing the overall configuration of the stator 1, and FIG. 1B is an exploded perspective view showing a part of the stator 1.

  The stator 1 is formed by laminating and integrating thin electromagnetic steel plates in the axial direction, and includes an annular back yoke portion 11 and salient pole portions 12 protruding from the inner peripheral surface of the back yoke portion 11. A plurality of salient pole portions 12 are formed at predetermined intervals in the circumferential direction of the back yoke portion 11, and the flat conductor rod 2 is inserted into a slot 13 formed between adjacent salient pole portions.

  The conductor rod 2 is formed with an insulating layer on the side surface in contact with the salient pole portion 12, and the power module 3 is provided at both axial ends thereof. The axial length of the conductor rod 2 is shorter than the axial length of the salient pole portion 12 so that the conductor rod 2 does not protrude from the slot 13 when the conductor rod 2 is inserted into the slot 13.

  FIG. 2 is a diagram showing an electric circuit composed of the conductor rod 2 and the power module 3.

  As shown in FIG. 2, the power module 3 includes two semiconductor switches and two diodes, and these switches are combined to form two switches SW1 and SW2.

  Each power module 3 is connected to a plus terminal and a minus terminal of a DC power source and is also electrically connected to the conductor rod 2, and an H-bridge driver circuit is formed by two power modules 3 at both ends of the conductor rod 2. The direction of the current flowing through the conductor rod 2 is switched.

  Specifically, the switch SW1 of the power module 3 on one end side (upper side in the figure) of the conductor rod 2 is turned on, the switch SW2 is turned off, and the switch SW1 of the power module 3 on the other end side (lower side in the figure) is turned off. When the switch SW2 is turned on, a current flows in the direction of arrow A from one end side of the conductor rod 2 toward the other end side. Conversely, when the switch SW1 of the power module 3 on one end side of the conductor rod 2 is turned off, the switch SW2 is turned on, the switch SW1 of the power module 3 on the other end side is turned on, and the switch SW2 is turned off, A current flows in the direction of arrow B from the end side toward the one end side. The switches SW1 and SW2 of each power module 3 are switched on and off by inputting a pulse wave to the semiconductor switch 31 as an input signal and changing the duty ratio of the pulse wave.

  FIG. 3 is a cross-sectional view of the rotating electrical machine 10 using the stator 1 in which the conductor rod 2 according to the present embodiment is inserted.

  As shown in FIG. 3, the rotating electrical machine 10 includes a cylindrical housing 4, and the rotating shaft 6 is rotatably supported by bearings 5 provided at both ends in the axial direction of the housing 4.

  A rotor 7 that rotates integrally with the rotation shaft 6 is fixed to the rotation shaft 6. A plurality of permanent magnets are embedded in the outer peripheral portion of the rotor 7 at predetermined intervals in the circumferential direction.

  The stator 1 is fixed to the housing 4 so as to cover the outer periphery of the rotor 7.

  The power module 3 protrudes in the axial direction from both ends of the stator 1, and each power module 3 at both ends is connected to a DC power source via a driver portion 8 provided in the housing 4. The driver unit 8 is disposed adjacent to the power modules 3 at both ends in the axial direction of the stator 1, and generates an input signal to be input to the semiconductor switch of each power module 3.

  The rotating electrical machine 10 is configured as described above, and by switching the switches SW1 and SW2 of the power module 3 provided at both ends of the conductor rod 2, the direction of the current flowing through the conductor rod 2 is switched and a rotating magnetic field is applied to the stator 1. The rotor 7 is rotated by attracting and repelling the permanent magnet of the rotor 7. Thereby, the rotating shaft 6 rotates together with the rotor 7.

  FIG. 4 is a schematic configuration diagram of an electric vehicle equipped with the rotating electrical machine 10 according to the present embodiment. As a comparative example, FIG. 12 shows a schematic configuration diagram of an electric vehicle equipped with a rotating electrical machine 100 configured by winding a coil 102 around a salient pole portion.

  As shown in FIG. 12, in the electric vehicle of the comparative example, an inverter 300 is separately provided between the DC power source 200 and the rotating electrical machine 100, and the DC from the DC power source 200 is converted into a three-phase AC by the inverter 300. The rotary electric machine 100 is driven by flowing through 100 coils 101.

  Here, the rotating electrical machine 100 according to the comparative example has end coils at both axial ends of the stator 101. The end coil does not contribute to generating a magnetic field for turning the magnetic pole on the rotor side of the salient pole part to N pole or S pole when energized, that is, a rotating magnetic field necessary for rotating the rotor 107. It becomes a source.

  For this reason, if the inverter 300 is disposed near the rotating electrical machine 100, particularly in the vicinity of both axial end portions of the stator 101, the leakage magnetic field may cause eddy current loss in the inverter components, and the driver circuit may be affected by noise. is there.

  Therefore, as shown in FIG. 12, in order to avoid the influence of the leakage magnetic field, it is necessary to separately provide the inverter 300 at a position away from the rotating electrical machine 100, and the motor system including the rotating electrical machine 100 and the inverter 300 can be downsized. I couldn't plan.

  On the other hand, when the rotating electrical machine 10 according to the present embodiment is used as shown in FIG. 4, there is no end coil, so the vicinity of both axial ends of the stator 1 in the rotating electrical machine (both ends of the conductor rod 2). ) Can be provided with a power module 3 and a driver unit 8 corresponding to an inverter. The direct current from the direct current power source 20 can be directly supplied to each power module 3 in the rotating electrical machine to drive the rotating electrical machine 10. Therefore, it is not necessary to separately provide an inverter between the DC power supply 20 and the rotating electrical machine 10, and the motor system can be reduced in size.

  In the electric vehicle according to the present embodiment, each power module 3 disposed on one axial end side (right side in the drawing) of the stator 1 is driven by a first feeder line 21a composed of a positive electric wire and a negative electric wire. It is connected to the DC power source 20 via the unit 8. On the other hand, each power module 3 arranged on the other axial end side (left side in the figure) of the stator 1 is connected to the DC power via the driver unit 8 by the second power supply line 21b that is also composed of a positive wire and a negative wire. Connected to the power supply 20.

  According to the present embodiment described above, the power module 3 is formed by inserting the conductor rod 2 into the slot 13 of the stator 1 and attaching it to both ends of the conductor rod 2 instead of winding the coil around the salient pole portion 12 of the stator 1. By switching the direction of the current flowing through the conductor rod 2, a rotating magnetic field is generated in the stator 1 and the rotor 7 is rotated. Therefore, there is no end coil as in the rotating electrical machine 100 of the comparative example.

  Therefore, the influence of the leakage magnetic field is small, and the power module 3 and the driver unit 8 corresponding to the inverter can be provided in the vicinity of both axial ends of the stator 1 in the rotating electrical machine (both ends of the conductor rod 2). Therefore, since it is not necessary to provide an inverter separately, the motor system can be downsized.

  Further, the length of the conductor rod 2 in the axial direction is made shorter than the length of the salient pole portion 12 in the axial direction so that the conductor rod 2 can be completely accommodated in the slot 13. Therefore, since the conductor rod 2 does not protrude in the axial direction from the upper end surface and the lower end surface of the salient pole portion 12, generation of a leakage magnetic field can be suppressed more reliably.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. The second embodiment of the present invention is different from the first embodiment in that the conductor rod 2 has a U-shape. Hereinafter, the difference will be mainly described. In addition, the description which overlaps using the same code | symbol to the part which fulfill | performs the same function as 1st Embodiment mentioned above is abbreviate | omitted suitably.

  FIG. 5 is a diagram illustrating the stator 1 according to the present embodiment. FIG. 5A is a perspective view showing the overall configuration of the stator 1, and FIG. 5B is an exploded perspective view showing a part of the stator 1.

  As shown in FIG. 5B, the conductor rod 2 according to the present embodiment has a U shape, and is inserted into the adjacent slots 13a and 13b so as to sandwich the salient pole portion 12. And the power module 3 is provided in the both ends of the conductor rod 2, respectively. Therefore, when the conductor rod 2 is inserted into the slot 13, the power module 3 is disposed only on one end side in the axial direction of the stator 1.

  FIG. 6 is a diagram showing an electric circuit composed of the conductor rod 2 and the power module 3 according to the present embodiment.

  As shown in FIG. 6, also in this embodiment, the two power modules 3 at both ends of the conductor rod 2 constitute an H-bridge driver circuit to switch the direction of the current flowing through the conductor rod 2. Specifically, the switch SW1 of the power module 3 on one end side (left side in the figure) of the conductor rod 2 is turned on, the switch SW2 is turned off, and the switch SW1 of the power module 3 on the other end side (right side in the figure) is turned off. When the switch SW2 is turned on, a current flows in the direction of arrow A from one end side of the conductor rod 2 toward the other end side. Conversely, when the switch SW1 of the power module 3 on one end side of the conductor rod 2 is turned off, the switch SW2 is turned on, the switch SW1 of the power module 3 on the other end side is turned on, and the switch SW2 is turned off, A current flows in the direction of arrow B from the end side toward the one end side.

  FIG. 7 is a schematic configuration diagram of an electric vehicle equipped with a rotating electrical machine 10 using the stator 1 in which the conductor rod 2 according to the present embodiment is inserted.

  As shown in FIG. 7, in the rotating electrical machine 10 according to the present embodiment, the power module 3 and the driver unit 8 are disposed only on one axial end side (right side in the drawing) of the stator 1. Therefore, the power supply line connected to the power module 3 may be only the first power supply line 21a.

  According to the present embodiment described above, since there is no end coil on one end side in the axial direction of the stator 1, it corresponds to an inverter in the vicinity of one end portion in the axial direction of the stator 1 in the rotating electrical machine (one end of the conductor rod 2). The power module 3 and the driver unit 8 can be provided. Therefore, it is not necessary to provide an inverter separately, so that the motor system can be reduced in size.

  In addition, since the power module 3 and the driver unit 8 are disposed only on one axial end side of the stator 1, the power supply line for electrically connecting the DC power supply 20 and the power module 3 may be only the first power supply line 21a. .

(Third embodiment)
Next, a third embodiment of the present invention will be described. The third embodiment of the present invention is different from the first embodiment in the configuration of the conductor rod 2. Hereinafter, the difference will be mainly described.

  In the case of the rotating electrical machine 10 configured by inserting one conductor rod 2 into each slot 13 of the stator 1, the cross-sectional area of the conductor rod 2 is set to the salient pole portion 12 a plurality of times as in the rotating electrical machine 100 of the comparative example. It becomes larger than the cross-sectional area of the coil 101 to be wound. Therefore, the eddy current loss that occurs in the conductor rod tends to be larger than the eddy current loss that occurs in the coil.

  In order to suppress the eddy current loss in the conductor rod 2, the conductor rod 2 is manufactured by bundling the mutually insulated wires, or the conductor rod 2 is manufactured by laminating thin conductor plates whose surfaces are insulated. However, in any case, the manufacturing method becomes complicated and costs increase. Then, the conductor bar 2 which can suppress generation | occurrence | production of an eddy current can be simply manufactured by manufacturing the conductor bar 2 with the following method.

  FIG. 8 is a diagram for explaining the conductor rod 2 and the manufacturing method thereof according to the present embodiment.

  In this embodiment, first, as shown in FIG. 8A, the conductor rod 2 such as copper or aluminum provided with a plurality of slits 21 in the axial direction is extruded so as to be larger than the shape of the slot 13. Manufactured by molding.

  Next, as shown in FIG. 8B, an organic coating such as tetrafluoroethylene resin (PTEF) or an inorganic coating is applied to the side surface of the conductor rod 2 including the slit 21 to form the insulating layer 22.

  Finally, as shown in FIG. 8C, the conductor rod 2 formed with the insulating layer 22 is drawn according to the shape of the slot 13, whereby the conductor rod 2 to be inserted into the slot 13 is manufactured.

  Thereby, since the insulation part 23 is formed inside the conductor rod 2, generation | occurrence | production of an eddy current can be suppressed. In addition, as a manufacturing method, only the draw molding is performed after the extrusion molding, so that the conductor rod 2 can be easily manufactured.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. The fourth embodiment of the present invention is different from the first embodiment in that a through hole 24 penetrating in the axial direction is provided inside the conductor rod 2. Hereinafter, the difference will be mainly described with reference to FIGS. 9 and 10.

  FIG. 9 is a perspective view of the conductor rod 2 according to the present embodiment. FIG. 10 is a perspective view of the conductor rod 2 provided with the power module 3 at both ends according to the present embodiment.

  As described above, the eddy current loss occurring in the conductor rod tends to be larger than the eddy current loss occurring in the coil. Therefore, in this embodiment, as shown in FIG. 9, two through holes 24 that penetrate in the axial direction are provided inside the conductor rod 2. Thereby, since generation | occurrence | production of the eddy current in a conductor rod can be suppressed, the eddy current loss in a conductor rod can be reduced.

  As shown in FIG. 10, in this embodiment, the ventilation holes 31 are provided in the power module 3 provided at both ends of the conductor rod 2 in which the through holes 24 are formed. As a result, air can be passed through the conductor rod 2. Therefore, the conductor rod 2 can be cooled, and eddy current loss in the conductor rod can be further reduced.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described. The fifth embodiment of the present invention is different from the second embodiment in that the stator 1, the conductor rod 2, the power module 3, and the driver portion 8 are sealed and integrated with a resin 9. Hereinafter, the difference will be mainly described.

  FIG. 11 is a cross-sectional view of the rotating electrical machine 10 according to the present embodiment.

  As shown in FIG. 11, in this embodiment, a U-shaped conductor rod 2 is inserted into a slot 13, and one end side in the axial direction of the stator 1 is provided at both ends of the conductor rod 2 (right side in the figure). The power module 3 arranged in () and the driver unit 8 arranged adjacent to the power module 3 were sealed with a resin 9. Thereby, since the stator 1, the conductor rod 2, the power module 3, and the driver part 8 can be integrated, the assembly | attachment to the housing 4 becomes easy.

  Moreover, since the heat generated in each part can be transmitted to the housing 4 through the resin 9, the heat dissipation performance can be improved.

  Note that the present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

1 Stator 2 Conductor Rod 3 Power Module (Semiconductor Element)
7 Rotor 11 Back yoke part 12 Salient pole part 24 Through hole

Claims (5)

A stator having an annular back yoke portion and a plurality of salient pole portions projecting from an inner peripheral surface of the back yoke portion; an outer periphery is covered by the stator, and is rotated by a rotating magnetic field generated in the stator. rotor and a flat plate-like conductor rods to be inserted in isolation between every said salient pole portion, provided on the rotor rotation axis direction end portion of the conductor rod, the conductor rod to the rotating magnetic field is generated in the stator And a semiconductor element that alternately switches the direction of the current flowing through the motor system.   The electric motor system according to claim 1, wherein the semiconductor element is provided on both ends of the conductor rod in the rotor rotation axis direction. A stator having an annular back yoke portion and a plurality of salient pole portions projecting from an inner peripheral surface of the back yoke portion; an outer periphery is covered by the stator, and is rotated by a rotating magnetic field generated in the stator. A U-shaped conductor rod inserted so as to sandwich the salient pole portion between the rotor and the adjacent salient pole portion, and provided at the end of the conductor rod in the rotor rotation axis direction, and rotated by the stator A semiconductor element that alternately switches the direction of the current flowing through the conductor rod so that a magnetic field is generated, and both ends of the conductor rod are arranged only on one end side in the rotor rotation axis direction of the stator, Electric motor system.     4. The electric motor system according to claim 1, wherein the conductor rod includes a through-hole penetrating in the rotor rotation axis direction. 5. 5. The electric motor according to claim 1, wherein the length of the conductor rod in the rotor shaft rotation direction is shorter than the length of the salient pole portion in the rotor shaft rotation direction. 6. system.

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