Rotary electric machine

Abstract

To provide a rotary electric machine that can prevent an excessive increase in the electric potential of a housing that accommodates a motor and a power supply unit, while stabilizing the operation of a control unit.SOLUTION: A rotary electric machine comprises: a motor unit; a power supply unit that supplies current to the motor unit; a housing that accommodates the motor unit and the power supply unit; a ground line that is grounded and connected to the housing; and a relay unit that is provided on the ground line. The ground line has a first ground line that connects the housing and the relay unit to each other, and a second ground line that is grounded and connected to the relay unit. When the electric potential of the housing is less than a relay electric potential, the relay unit electrically cuts off the first ground line and the second ground line from each other, and when the electric potential of the housing is equal to or more than the relay electric potential, electrically connects the first ground line and the second ground line to each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a rotating electrical machine.

Background Art

[0002] There is known a motor drive system that suppresses noise generated in a motor from propagating to an inverter circuit via an earth wire and the earth by passing a ferrite core through the earth wire connecting a housing that houses a motor supplied with an alternating current from an inverter circuit and the earth (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the motor drive system as described above, for example, it is difficult to suppress the propagation of conductive noise having a frequency of several MHz or less to the inverter circuit, and thus there is a risk that the conductive noise propagates to a control unit that controls the operation of the inverter circuit. When the conductive noise propagates to the control unit, the operation of the control unit becomes unstable, so that the current supplied to the motor becomes unstable and the operation of the motor may not be stable.

[0005] One object of one aspect of the present invention is to provide a rotating electrical machine that can suppress the potential of a housing that houses a motor and a power supply unit from becoming too high while stabilizing the operation of the control unit.

Means for Solving the Problems

[0006] One aspect of the rotating electrical machine of the present invention includes a motor unit, a power supply unit that supplies current to the motor unit, a housing that houses the motor unit and the power supply unit, a ground line that is grounded and connected to the housing, and a relay unit provided on the ground line. The ground line has a first ground line that connects the housing and the relay unit, and a second ground line that is grounded and connected to the relay unit. The relay unit electrically disconnects the first ground line and the second ground line when the potential of the housing is less than the relay potential, and electrically connects the first ground line and the second ground line when the potential of the housing is greater than or equal to the relay potential.

Advantages of the Invention

[0007] According to the rotating electrical machine of the present embodiment, it is possible to suppress the potential of the housing that houses the motor and the power supply unit from becoming too high while stabilizing the operation of the control unit.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0009] Hereinafter, a rotating electrical machine according to an embodiment of the present invention will be described with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments and can be arbitrarily changed within the scope of the technical idea of the present invention. Also, in the following drawings, in order to make each configuration easier to understand, there may be cases where the actual structure, scale, number, etc. are different.

[0010] FIG. 1 is a schematic diagram showing a rotating electrical machine 10 according to the present embodiment. The rotating electrical machine 10 is a drive device mounted on a vehicle and rotates the vehicle axle. The vehicle on which the rotating electrical machine 10 is mounted is a vehicle having a motor unit 20 as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), or an electric vehicle (EV). In the present embodiment, the rotating electrical machine 10 includes a housing 15, a motor unit 20, a power supply unit 30, a control unit 26, a ground line 45, and a relay unit 28.

[0011] The housing 15 houses the motor unit 20 and the power supply unit 30 inside. In the present embodiment, the housing 15 has a motor housing 16, a power supply housing 17, and a heat sink 18. In the present embodiment, the motor housing 16, the power supply housing 17, and the heat sink 18 are electrically connected to each other. The motor housing 16, the power supply housing 17, and the heat sink 18 may not be electrically connected to each other.

[0012] The motor housing 16 houses the motor unit 20 inside. In the present embodiment, the motor housing 16 is made of metal. The motor housing 16 has conductivity. The power supply housing 17 houses the power supply unit 30 inside. The power supply housing 17 may be made of a metal material or a resin material. The heat sink 18 is disposed inside the power supply housing 17. In the present embodiment, the heat sink 18 is made of metal. The heat sink 18 has conductivity. The heat sink 18 holds a power module unit 33 described later. The heat sink 18 dissipates heat generated in the power module unit 33.

[0013] The motor unit 20 is housed inside the motor housing 16. The motor unit 20 is connected to the vehicle axle of the vehicle described above. The motor unit 20 rotates the vehicle axle. The motor unit 20 has a rotor (not shown) and a stator. The stator has a plurality of coil parts 21. The plurality of coil parts 21 each include a U-phase coil, a V-phase coil, and a W-phase coil. When an alternating current is supplied from the power supply unit 30 to each coil part 21, a rotor (not shown) rotates. The rotation of the rotor is transmitted to the vehicle axle of the vehicle.

[0014] When alternating current power is supplied to each coil part 21, noise is generated in each coil part 21. The noise generated in each coil part 21 propagates to the motor housing 16 through the parasitic capacitance formed between each coil part 21 and the motor housing 16.

[0015] The power supply unit 30 generates a supply current from the current supplied from the external power supply 25 and supplies the supply current to each coil part 21 of the motor unit 20. In the present embodiment, the supply current is an alternating current or a direct current. The power supply unit 30 has a plurality of diodes 31, a capacitor 32, and a power module unit 33.

[0016] Each of the plurality of diodes 31 is electrically connected to the external power supply 25 via a power line 41. The plurality of diodes 31 rectify the current supplied from the external power supply 25. The capacitor 32 smoothes the current flowing into the power module unit 33.

[0017] The power module unit 33 generates a supply current from the current supplied from the external power source 25. That is, the power module unit 33 generates a current to be supplied to the motor unit 20. The power module unit 33 is electrically connected to each coil unit 21 of the motor unit 20 via the motor line 42. Thereby, the power module unit 33 supplies the supply current to each coil unit 21. In the present embodiment, the power module unit 33 has a plurality of switching elements (not shown). The switching elements are, for example, power semiconductor elements such as insulated gate bipolar transistors (IGBTs: Insulated Gate Bipolar Transistors) and MOSFETs (Metal - Oxide - Semiconductor Field - Effect Transistors, metal oxide semiconductor field effect transistors). The switching elements generate a supply current from the current supplied from the external power source 25.

[0018] When the switching elements generate a supply current, heat is generated in the switching elements. Thereby, the temperature of the power module unit 33 rises. As described above, the power module unit 33 is held by the heat sink 18. The heat of the power module unit 33 is radiated into the air via the heat sink 18. The heat of the power module unit 33 may be radiated to the refrigerant circulating through the power housing 17 via the heat sink 18. Also, when the switching elements generate a supply current, noise is generated. The noise generated in the power module unit 33 propagates to the heat sink 18 through the parasitic capacitance formed between the power module unit 33 and the heat sink 18.

[0019] The control unit 26 is electrically connected to each of the plurality of switching elements included in the power module unit 33 via the control line 44. The control unit 26 controls the operation of each switching element. Thereby, the frequency and amplitude of the supply current generated by the power module unit 33 can be set to desired frequencies and amplitudes. In the present embodiment, the control unit 26 is, for example, a microcomputer.

[0020] The external power source 25 is a power source possessed by the vehicle. The external power source 25 is, for example, a battery possessed by the vehicle. In the present embodiment, the external power source 25 supplies a direct current to the power supply unit 30. The external power source 25 may supply an alternating current to the power supply unit 30. The external power source 25 is electrically connected to the power supply unit 30 via the power line 41. In the present embodiment, the rotating electrical machine 10 has two power lines 41. Each power line 41 is connected in parallel between the external power source 25 and the power supply unit 30. Also, the external power source 25 is grounded via the power ground line 43.

[0021] One end of the ground line 45 is connected to the housing 15, and the other end of the ground line 45 is grounded. Thereby, the housing 15 is grounded via the ground line 45. The ground line 45 has a first ground line 46 and a second ground line 48.

[0022] One end of the first ground line 46 is connected to the housing 15, and the other end of the first ground line 46 is connected to the relay portion 28. Thereby, the first ground line 46 connects the housing 15 and the relay portion 28. The potential of the first ground line 46 is the same as the potential Vh of the housing 15. One end of the second ground line 48 is connected to the relay portion 28, and the other end of the second ground line 48 is grounded. Thereby, the relay portion 28 is grounded via the second ground line 48. Thus, the housing 15 is grounded via the first ground line 46, the relay portion 28, and the second ground line 48. The first ground line 46 has a first branch portion 46a, a second branch portion 46b, and a confluence portion 46c.

[0023] One end of the first branch portion 46a is connected to the motor housing 16. Thereby, the ground line 45 is connected to the motor housing 16. The other end of the first branch portion 46a is connected to one end of the confluence portion 46c. One end of the second branch portion 46b is connected to the heat sink 18. Thereby, the ground line 45 is connected to the heat sink 18. The other end of the second branch portion 46b is connected to one end of the confluence portion 46c. The other end of the confluence portion 46c is connected to the relay portion 28. As described above, the relay portion 28 is grounded via the second ground line 48. Therefore, in the present embodiment, each of the motor housing 16 and the heat sink 18 is grounded.

[0024] The relay portion 28 is provided on the ground line 45. The relay portion 28 is grounded via the second ground line 48. The relay portion 28 controls the electrical connection between the first ground line 46 and the second ground line 48. More specifically, when the potential of the first ground line 46, that is, the potential Vh of the housing 15 is less than the relay potential Vr, the relay portion 28 electrically disconnects the first ground line 46 and the second ground line 48. When the potential of the housing 15 is equal to or higher than the relay potential Vr, the relay portion 28 electrically connects the first ground line 46 and the second ground line 48. In the present embodiment, the relay portion 28 has at least one of a varistor, a Zener diode, a relay, and a photocoupler. The relay portion 28 may have one of a varistor, a Zener diode, a relay, and a photocoupler, or may have a plurality of any of a varistor, a Zener diode, a relay, and a photocoupler. Further, the relay portion 28 may have two or more of a varistor, a Zener diode, a relay, and a photocoupler.

[0025] When the relay unit 28 has a varistor, the relay potential Vr is the varistor voltage. When the potential Vh of the housing 15 is less than the relay potential Vr, that is, when the potential Vh of the housing 15 is less than the varistor voltage, the relay unit 28 electrically disconnects the first ground line 46 and the second ground line 48. When the potential Vh of the housing 15 is greater than or equal to the relay potential Vr, that is, when the potential Vh of the housing 15 is greater than or equal to the varistor voltage, the electrical resistance of the relay unit 28 decreases, so the first ground line 46 and the second ground line 48 are electrically connected.

[0026] When the relay unit 28 has a Zener diode, the relay potential Vr is the Zener voltage. When the potential Vh of the housing 15 is less than the relay potential Vr, that is, when the potential Vh of the housing 15 is less than the Zener voltage, the relay unit 28 electrically disconnects the first ground line 46 and the second ground line 48. Also, when the potential Vh of the housing 15 is greater than or equal to the relay potential Vr, that is, when the potential Vh of the housing 15 is greater than or equal to the Zener voltage, the electrical resistance of the relay unit 28 decreases, so the first ground line 46 and the second ground line 48 are electrically connected.

[0027] When the relay unit 28 has a relay, the relay potential Vr is the voltage at which the coil of the relay drives the contact part, that is, the coil voltage. In the present embodiment, when the potential Vh of the housing 15 is less than the relay potential Vr, that is, when the potential Vh of the housing 15 is less than the coil voltage, the contact part is in an open state, so the relay unit 28 electrically disconnects the first ground line 46 and the second ground line 48. Also, when the potential Vh of the housing 15 is greater than or equal to the relay potential Vr, that is, when the potential Vh of the housing 15 is greater than or equal to the coil voltage, the coil drives the contact part, and the contact part becomes a closed state. Thereby, the relay unit 28 electrically connects the first ground line 46 and the second ground line 48.

[0028] When the relay unit 28 has an optocoupler, the relay potential Vr is the voltage at which a light-emitting element such as a light-emitting diode included in the optocoupler emits light. In the present embodiment, when the potential Vh of the housing 15 is less than the relay potential Vr, the light-emitting element does not emit light, so the contact portion connected to the light-receiving element is in an open state. As a result, the relay unit 28 electrically disconnects the first ground line 46 and the second ground line 48. When the potential Vh of the housing 15 is equal to or higher than the relay potential Vr, the light-emitting element emits light, so the contact portion connected to the light-receiving element is in a closed state. As a result, the relay unit 28 electrically connects the first ground line 46 and the second ground line 48.

[0029] In the present embodiment, the relay potential Vr is 30 V or higher and 35 V or lower. When a user or the like of the rotating electric machine 10 touches the charged housing 15, the user or the like gets an electric shock. When the user or the like touches the housing 15 charged to a potential greater than 35 V, there is a risk that the user or the like will be injured by the electric shock.

[0030] FIG. 2 is a schematic diagram showing noise N in the rotating electric machine 110 of the comparative example. Compared with the rotating electric machine 10 of the present embodiment, the rotating electric machine 110 of the comparative example does not include the relay unit 28. Therefore, in the rotating electric machine 110 of the comparative example, the housing 15 is constantly grounded via the ground line 45. Other configurations of the rotating electric machine 110 of the comparative example are the same as those of the rotating electric machine 10 of the present embodiment described above.

[0031] During the operation of the rotating electric machine 110, as described above, noise N is generated in each coil unit 21. The noise N generated in each coil unit 21 propagates to the motor housing 16 through the parasitic capacitance formed between each coil unit 21 and the motor housing 16. During the operation of the rotating electric machine 110, as described above, noise N is generated in the power module unit 33. The noise N generated in the power module unit 33 propagates to the heat sink 18 through the parasitic capacitance formed between the power module unit 33 and the heat sink 18. That is, during the operation of the rotating electric machine 110, noise N propagates to the housing 15.

[0032] As described above, since the rotating electrical machine 110 does not include the relay unit 28, the housing 15 is constantly grounded via the ground line 45. Therefore, the noise N propagated to each of the motor housing 16 and the heat sink 18 propagates to the ground E via the ground line 45. The noise N propagated to the ground E propagates to the power supply unit 30 via the power supply ground line 43, the external power supply 25, and the power supply line 41. The noise N propagated to the power supply unit 30 propagates to the control unit 26 via the control line 44. That is, the noise N generated in the motor unit 20 and the power supply unit 30 constantly propagates to the control unit 26 via the ground line 45, the ground E, the external power supply 25, and the power supply unit 30. When the noise N propagates to the control unit 26, the operation of the control unit 26 becomes unstable. As a result, the operation of each of the plurality of switching elements included in the power module unit 33 controlled by the control unit 26 becomes unstable, so that the waveform of the supply current generated by the power module unit 33 may deviate from the desired waveform. When the waveform of the supply current supplied to each coil unit 21 deviates from the desired waveform, the operation of the motor unit 20 may not be stable. As described above, in the rotating electrical machine 110 of the comparative example, since the housing 15 is constantly grounded via the ground line 45, the noise N constantly propagates to the control unit 26. Therefore, the operation of the motor unit 20 may not be constantly stable.

[0033] FIG. 3 is a schematic diagram showing the noise N in the rotating electrical machine 10 of the present embodiment. In FIG. 3, the potential Vh of the housing 15 is less than the relay potential Vr. FIG. 4 is a schematic diagram showing the flow of the discharge current Ir in the rotating electrical machine 10 of the present embodiment. In FIG. 4, the potential Vh of the housing 15 is equal to or higher than the relay potential Vr.

[0034] As described above, in the present embodiment, when the potential of the housing 15 is less than the relay potential Vr, the relay unit 28 disconnects the first ground line 46 and the second ground line 48. Therefore, in the rotating electric machine 10 of the present embodiment, as shown in FIG. 3, it is possible to suppress the noise N propagated to each of the motor housing 16 and the heat sink 18 from propagating to the ground E via the second ground line 48. Therefore, when the potential of the housing 15 is less than the relay potential Vr, it is possible to suppress the noise N generated in each of the motor unit 20 and the control unit 26 from propagating to the control unit 26, so that the operation of the motor unit 20 can be stabilized. At this time, since each of the motor housing 16 and the heat sink 18 is not grounded, charges are accumulated in each of the motor housing 16 and the heat sink 18. As a result, the potential of each of the motor housing 16 and the heat sink 18 increases. That is, the potential Vh of the housing 15 increases.

[0035] As described above, in the present embodiment, when the potential Vh of the housing 15 is equal to or higher than the relay potential Vr, the relay unit 28 connects the first ground line 46 and the second ground line 48. Therefore, in the rotating electric machine 10 of the present embodiment, when the potential Vh of the housing 15 rises to be equal to or higher than the relay potential Vr, the housing 15 is grounded via the ground line 45. Therefore, as shown in FIG. 4, a discharge current Ir flows from each of the motor housing 16 and the heat sink 18 to the ground E via the ground line 45. That is, in the rotating electric machine 10 of the present embodiment, when the potential Vh of the housing 15 becomes equal to or higher than the relay potential Vr, a discharge current Ir flows from the housing 15 to the ground E. As a result, the potential Vh of the housing 15 can be decreased, so that it is possible to suppress the potential Vh of the housing 15 from becoming larger than the relay potential Vr. When the potential Vh of the housing 15 decreases to less than the relay potential Vr, the relay unit 28 disconnects the first ground line 46 and the second ground line 48.

[0036] When the first ground line 46 and the second ground line 48 are connected, as described above, the noise N generated in each of the motor unit 20 and the control unit 26 propagates to the control unit 26. However, in the present embodiment, the first ground line 46 and the second ground line 48 are connected only when the potential Vh of the housing 15 is equal to or higher than the relay potential Vr. Therefore, compared with the rotating electric machine 110 of the comparative example in which the first ground line 46 and the second ground line 48 are constantly connected, the frequency at which the operation of the control unit 26 becomes unstable can be reduced. Accordingly, compared with the rotating electric machine 110 of the comparative example, the operation of the motor unit 20 can be stabilized.

[0037] According to this embodiment, the rotating electrical machine 10 includes a motor unit 20, a power supply unit 30 that supplies current to the motor unit 20, a housing 15 that houses the motor unit 20 and the power supply unit 30, a ground line 45 that is grounded and connected to the housing 15, and a relay unit 28 provided on the ground line 45. The ground line 45 has a first ground line 46 that connects the housing 15 and the relay unit 28, and a second ground line 48 that is grounded and connected to the relay unit 28. When the potential Vh of the housing 15 is less than the relay potential Vr, the relay unit 28 electrically disconnects the first ground line 46 and the second ground line 48, and when the potential Vh of the housing 15 is greater than or equal to the relay potential Vr, the relay unit 28 electrically connects the first ground line 46 and the second ground line 48. Therefore, when the potential Vh of the housing 15 is less than the relay potential Vr, the housing 15 is not grounded via the ground line 45. Thus, as described above, it is possible to suppress the noise N generated in the motor unit 20 and the power supply unit 30 from constantly propagating to the control unit 26 via the ground line 45, the earth E, the external power supply 25, and the power supply unit 30. Thereby, the operation of the control unit 26 can be stabilized, so that a supply current having a desired waveform can be constantly supplied to the motor unit 20. Therefore, the operation of the motor unit 20 can be stabilized, and thus the operation of the rotating electrical machine 10 can be stabilized. Further, when the potential Vh of the housing 15 is greater than or equal to the relay potential Vr, the housing 15 is grounded via the ground line 45. Thus, as described above, a discharge current Ir can be made to flow from the housing 15 to the earth E. Therefore, it is possible to suppress the potential Vh of the housing 15 from becoming greater than the relay potential Vr. Thereby, it is possible to suppress the potential Vh of the housing 15 from becoming too high, so that even if a user or the like touches the housing 15, it is possible to suppress the user or the like from being injured.

[0038] The ground line 45 is a line for grounding the housing 15, and the power line 41 is a line through which the current supplied from the external power source 25 to the power supply unit 30 flows. Therefore, it is easy to make the current capacity of the ground line 45 smaller than that of the power line 41. Also, as described above, the rotating electrical machine 10 includes two power lines 41. Therefore, for example, by providing the relay section 28 in each power line 41, compared with the rotating electrical machine having a configuration that suppresses the propagation of the noise N to the control section 26, in the rotating electrical machine 10 of the present embodiment, the current capacity of the relay section 28 can be made smaller and the number of relay sections 28 can be reduced. As a result, it is possible to suppress the increase in the size of the relay section 28 and to suppress the increase in the manufacturing cost of the relay section 28. Therefore, it is possible to suppress the increase in the size of the rotating electrical machine 10 and to suppress the increase in the manufacturing cost of the rotating electrical machine 10.

[0039] According to the present embodiment, the housing 15 has a motor housing 16 that houses the motor section 20, and the ground line 45 is connected to the motor housing 16. Therefore, when the potential of the motor housing 16 is less than the relay potential Vr, it is possible to suppress the noise N generated in the motor section 20 from constantly propagating to the control section 26 via the motor housing 16, the ground line 45, the ground E, the external power source 25, and the power supply unit 30. Therefore, as described above, since the operation of the control section 26 can be stabilized, the operation of the motor section 20 can be stabilized. Also, when the potential of the motor housing 16 is equal to or higher than the relay potential Vr, since the motor housing 16 is grounded via the ground line 45, it is possible to flow a discharge current Ir from the motor housing 16 to the ground E. Therefore, since it is possible to suppress the potential of the motor housing 16 from becoming too high, it is possible to suppress the user or the like from being injured even if the user or the like touches the motor housing 16.

[0040] According to this embodiment, the power supply unit 30 has a power module unit 33 that generates a current to be supplied to the motor unit 20, the housing 15 has a heat sink 18 that dissipates the heat of the power module unit 33, and the ground line 45 is connected to the heat sink 18. Therefore, when the potential of the heat sink 18 is less than the relay potential Vr, it is possible to suppress the noise N generated in the power supply unit 30 from constantly propagating to the control unit 26 via the heat sink 18, the ground line 45, the ground E, the external power supply 25, and the power supply unit 30. Therefore, as described above, since the operation of the control unit 26 can be stabilized, the operation of the motor unit 20 can be stabilized.

[0041] According to this embodiment, the relay potential Vr is 30 V or more and 35 V or less. When the relay potential Vr is too small, the frequency of connection between the first ground line 46 and the second ground line 48 increases, so the frequency of the noise N generated in each of the motor unit 20 and the power supply unit 30 propagating to the control unit 26 increases. As a result, the frequency of the operation of the control unit 26 becoming unstable increases, making it difficult to stabilize the operation of the motor unit 20. When the relay potential Vr is too large, the potential Vh of the housing 15 tends to increase, so if a user or the like touches the housing 15, there is a risk of the user or the like being injured. On the other hand, in this embodiment, as described above, since the relay potential Vr is 30 V or more and 35 V or less, it is possible to suppress the relay potential Vr from becoming too small. Thereby, it is possible to suppress an increase in the frequency of connection between the first ground line 46 and the second ground line 48, so that it is possible to suppress an increase in the frequency of the noise N generated in each of the motor unit 20 and the power supply unit 30 propagating to the control unit 26. As a result, it is possible to suppress an increase in the frequency of the operation of the control unit 26 becoming unstable, so that the operation of the motor unit 20 can be stabilized. Also, since it is possible to suppress the relay potential Vr from becoming too large, it is possible to suppress the potential Vh of the housing 15 from becoming too large. Therefore, even if a user or the like touches the housing 15, it is possible to suppress the user or the like from being injured.

[0042] According to this embodiment, the relay unit 28 includes at least one of a varistor, a Zener diode, a relay, and a photocoupler. Therefore, since the relay unit 28 can be constituted by general-purpose electronic components, it is possible to more preferably suppress an increase in the manufacturing cost of the relay unit 28.

[0043] The present invention is not limited to the above-described embodiment, and other configurations and other methods can be adopted within the scope of the technical idea of the present invention. The ground line may be connected to the power supply housing in addition to the motor housing and the heat sink. Thereby, since it is possible to suppress the potential of the power supply housing from becoming too large, it is possible to suppress the user from being injured when the user touches the power supply housing. Further, the ground line may not be connected to either the motor housing or the heat sink.

[0044] The relay potential is not limited to this embodiment. For example, it may be less than 30V or may be greater than 35V. Further, the relay unit may include electronic components other than a varistor, a Zener diode, a relay, and a photocoupler.

[0045] As described above, the embodiments of the present invention have been described. However, each configuration and their combinations in the embodiments are examples, and additions, omissions, substitutions, and other changes of the configuration are possible without departing from the spirit of the present invention. Further, the present invention is not limited by the embodiments.

[0046] Note that the present technology can be configured as follows. (1) A rotating electrical machine comprising a motor unit, a power supply unit that supplies current to the motor unit, a housing that houses the motor unit and the power supply unit, a ground line that is grounded and connected to the housing, and a relay unit provided on the ground line. The ground line has a first ground line that connects the housing and the relay unit, and a second ground line that is grounded and connected to the relay unit. The relay unit electrically disconnects the first ground line and the second ground line when the potential of the housing is less than the relay potential, and electrically connects the first ground line and the second ground line when the potential of the housing is greater than or equal to the relay potential. (2) The rotating electrical machine according to (1), wherein the housing has a motor housing that houses the motor unit, and the ground line is connected to the motor housing. (3) The rotating electrical machine according to (1) or (2), wherein the power supply unit has a power module unit that generates current supplied to the motor unit, the housing has a heat sink that dissipates heat of the power module unit, and the ground line is connected to the heat sink. (4) The rotating electrical machine according to any one of (1) to (3), wherein the relay potential is 30 V or more and 35 V or less. (5) The rotating electrical machine according to any one of (1) to (4), wherein the relay unit has at least one of a varistor, a Zener diode, a relay, and a photocoupler.

Explanation of Reference Numerals

[0047] 10... Rotating electrical machine, 15... Housing, 16... Motor housing, 18... Heat sink, 20... Motor unit, 28... Relay unit, 30... Power supply unit, 33... Power module unit, 45... Ground line, 46... First ground line, 48... Second ground line, Vh... Potential of housing, Vr... Relay potential

Claims

1. A motor unit, A power supply unit that supplies current to the motor unit, A housing that houses the motor unit and the power supply unit, A ground line that is grounded and connected to the housing, A relay unit provided on the ground line, Comprising, The ground line has a first ground line connecting the housing and the relay unit, and a second ground line that is grounded and connected to the relay unit, The relay unit, When the potential of the housing is less than the relay potential, electrically disconnects the first ground line and the second ground line, When the potential of the housing is equal to or higher than the relay potential, electrically connects the first ground line and the second ground line, a rotating electrical machine.

2. The housing has a motor housing that houses the motor unit, The ground line is connected to the motor housing, the rotating electrical machine according to claim 1.

3. The power supply unit has a power module unit that generates current supplied to the motor unit, The housing has a heat sink that dissipates heat from the power module unit, The ground line is connected to the heat sink, the rotating electrical machine according to claim 1.

4. The relay potential is 30 V or more and 35 V or less, the rotating electrical machine according to any one of claims 1 to 3.

5. The relay unit has at least one of a varistor, a Zener diode, a relay, and a photocoupler, the rotating electrical machine according to any one of claims 1 to 3.

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