Motor drive device

Abstract

A motor drive device is provided. The motor drive device (1) includes an electric storage device (3), a motor (5), a first inverter (10), a second inverter (20), and an external AC terminal (51). The motor drive device further includes a third inverter (30), a transformer (53) connected to an AC terminal of the third inverter (30), a first switch (15) capable of switching an AC terminal of the first inverter (10) to a state of being connected to one of a first winding connection portion (5a) of the motor and the external AC terminal (51), a second switch (25) capable of switching an AC terminal of the second inverter (20) to a state of being connected to one of a second winding connection portion (5b) of the motor and the transformer (53), and a third switch (35) capable of switching the electric storage device to a state of being connected to one of a DC terminal of the first inverter and a DC terminal of the second inverter and a DC terminal of the third inverter.

Description

TECHNICAL FIELD

[0001] The present application relates to a motor drive device. BACKGROUND

[0002] In recent years, as a specific countermeasure against global climate change, initiatives toward realization of a low-carbon society or a decarbonized society are very active. For vehicles as well, there is a strong demand for reduction in CO2 emissions, and electrification of drive sources is rapidly progressing. Specifically, development of vehicles such as an electrical vehicle (EV) or a hybrid electrical vehicle (HEV) that have an electric motor as a drive source, a storage battery as a secondary battery capable of supplying electric power to the electric motor, and an inverter as a power conversion device is being promoted.

[0003] For such a vehicle, it is necessary to downsize and lighten the entire system and improve energy efficiency.

[0004] For example, in Patent Literature 1, a motor drive device of a vehicle is described that uses an inverter for driving a motor at the time of charging from the outside.

[0005]

Prior Art Literature

[0006]

Patent Literature

[0007] Patent Literature 1: International Publication No. 2013 / 168491

[0008] However, in the motor drive device described in Patent Literature 1, many electronic components are used only for charging, and there is room for improvement. SUMMARY

[0009] The present application provides a motor drive device that can share a drive circuit and a charging circuit and can reduce the number of components.

[0010] The present application provides a motor drive device including:

[0011] a power storage device;

[0012] a motor including at least a first winding connection portion and a second winding connection portion;

[0013] a first inverter having a direct current terminal and an alternating current terminal for supplying electric power from the power storage device to the first winding connection portion;

[0014] a second inverter having a direct current terminal and an alternating current terminal for supplying electric power from the power storage device to the second winding connection portion; and

[0015] an external AC terminal capable of transmitting electric power between the electric storage device and an external AC power source,

[0016] wherein the motor drive device further has:

[0017] a third inverter having a DC terminal and an AC terminal;

[0018] a transformer connected to the AC terminal of the third inverter;

[0019] a first switch capable of switching the AC terminal of the first inverter to a state of being connected to either one of the first winding connection portion and the external AC terminal;

[0020] a second switch capable of switching the AC terminal of the second inverter to a state of being connected to either one of the second winding connection portion and the transformer; and

[0021] a third switch capable of switching the electric storage device to a state of being connected to either one of the DC terminal of the first inverter and the DC terminal of the second inverter and the DC terminal of the third inverter.

[0022] According to the present application, the drive circuit and the charging circuit can be shared, and thus the number of electronic components used only for charging and the number of electronic components used only for driving can be reduced, and the number of components can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a circuit diagram of the motor drive device 1 of the first embodiment.

[0024] Figure 2 is a diagram showing the flow of current when the motor is driven in the circuit diagram of the motor drive device 1 of the first embodiment.

[0025] Figure 3 is a diagram showing the flow of current when the external AC power source is connected in the circuit diagram of the motor drive device 1 of the first embodiment.

[0026] Figure 4 is a circuit diagram of the motor drive device 1 of the second embodiment and a diagram showing the flow of current when the external DC power source is connected in the circuit diagram.

[0027] Figure 5 is a circuit diagram of the motor drive device 1 of the third embodiment and a diagram showing the flow of current when the external DC power source is connected in the circuit diagram.

[0028] Figure 6 is a circuit diagram of the motor drive device 1 of the fourth embodiment.

[0029] Figure 7 is a circuit diagram of the motor drive device 1 of the fifth embodiment.

[0030] Figure 8 is a circuit diagram of the motor drive device 1 of the sixth embodiment and a diagram showing current flow when a non-contact charging device is connected in the circuit diagram.

[0031] Figure 9 is a circuit diagram of the motor drive device 1 of the first modification.

[0032] Figure 10 is a circuit diagram of the motor drive device 1 of the second modification.

[0033] --BRIEF DESCRIPTION OF THE DRAWINGS--

[0034] 1 motor drive device

[0035] 3 power storage device

[0036] 5 motor

[0037] 5a first winding connection portion

[0038] 5b second winding connection portion

[0039] 7 control device

[0040] 10 first inverter

[0041] 11 direct current terminal

[0042] 12 alternating current terminal

[0043] 15 first switch

[0044] 20 second inverter

[0045] 21 direct current terminal

[0046] 22 alternating current terminal

[0047] 25 second switch

[0048] 30 third inverter

[0049] 31 direct current terminal

[0050] 32 alternating current terminal

[0051] 35 third switch

[0052] 51 external alternating current terminal

[0053] 53 transformer

[0054] 61 external direct current terminal

[0055] 71 auxiliary machine connection circuit

[0056] 73 DC-DC converter (auxiliary machine)

[0057] 75 electric oil pump (auxiliary machine)

[0058] 81 non-contact charging device DETAILED DESCRIPTION

[0059] Hereinafter, each embodiment of the motor drive device of the present application will be described based on the drawings.

[0060] Figure 1 is a circuit diagram showing a motor drive device 1 of a first embodiment of the present application. The motor drive device 1 is provided with an electric storage device 3 (BAT), a motor 5, a first inverter 10 (INV1), a second inverter 20 (INV2), and an external AC terminal 51. The motor drive device 1 is further provided with a third inverter 30, a transformer 53, an inductor 54, a first switch 15, a second switch 25, and a third switch 35. The motor drive device 1, for example, converts a direct current from the electric storage device 3 mounted on a vehicle into an alternating current, and drives the motor 5 as a drive source. The motor drive device 1 stores electric power in the electric storage device 3 by power transmission from an external AC power source AC connected to the external AC terminal 51. The electric storage device 3, which is so-called battery, can use a lithium ion secondary battery, a nickel-hydrogen battery, or the like, and the kind thereof is not particularly limited.

[0061] The motor 5 is a double three-phase motor having two sets of three-phase winding connection portions. Each phase winding connection portion includes a first winding connection portion 5a connected to a first winding and a second winding connection portion 5b connected to a second winding. The winding connection portion is, for example, a terminal unit having terminals connected to one set of U-phase, V-phase, and W-phase three-phase windings. Although not shown in the drawing, the motor 5 is provided with a rotating rotor and a stator arranged at the outer periphery of the rotor. A plurality of teeth are arranged at a certain interval on the stator, and three-phase coils connected to the first winding connection portion 5a and three-phase coils connected to the second winding connection portion 5b are wound on the teeth. However, the kind of the motor 5 is not particularly limited, and a motor having three or more sets of winding connection portions can also be used. For example, as shown in a first modification of Figure 9 , the motor 5 can also be an open-type winding motor provided with two sets of three-phase winding connection portions. In addition, the number of the motor 5 can be one, or two as shown in a second modification of Figure 10 . If the motor drive device 1 is provided with two motors 5, it is preferable that each motor has one set of three-phase winding connection portions.

[0062] Returning to Figure 1The first inverter 10 has DC terminals 11, AC terminals 12, and three-phase arms connected in parallel, and is configured to be able to supply electric power from the electric storage device 3 to the first winding connection portion 5a. Each arm has a pair of switching elements, such as insulated gate bipolar transistors (IGBTs), connected in series, and a free-wheeling diode connected in parallel to each switching element. The DC terminals 11 of the first inverter 10 are connected to positive-side and negative-side wires of the three-phase arms connected in parallel, and are connected to the electric storage device 3 via the capacitor Cl and the third switch 35 described later. The AC terminals 12 of the first inverter 10 are connected to connection points between the pair of switching elements of each arm, and are connected to the first winding connection portion 5a of the motor 5 via the first switch 15 described later. Thus, the first inverter 10 is able to convert electric power of the electric storage device 3 as a DC power source into AC electric power, and supply the AC electric power to the first winding connection portion 5a of the motor 5 as an AC motor.

[0063] The second inverter 20 has DC terminals 21, AC terminals 22, and three-phase arms connected in parallel, and is configured to be able to supply electric power from the electric storage device 3 to the second winding connection portion 5b. Each arm has a pair of switching elements, such as IGBTs, connected in series, and a free-wheeling diode connected in parallel to each switching element. The DC terminals 21 of the second inverter 20 are connected to positive-side and negative-side wires of the three-phase arms connected in parallel, and are connected to the electric storage device 3 via the capacitor Cl and the third switch 35 described later. The AC terminals 22 of the second inverter 20 are connected to connection points between the pair of switching elements of each arm, and are connected to the second winding connection portion 5b of the motor 5 via the second switch 25 described later. Thus, the second inverter 20 is able to convert electric power of the electric storage device 3 as a DC power source into AC electric power, and supply the AC electric power to the second winding connection portion 5b of the motor 5 as an AC motor.

[0064] The first inverter 10 and the second inverter 20 constitute a power conversion unit 8 (PDU).

[0065] The external AC terminals 51 are able to transmit electric power between the electric storage device 3 and an external AC power source AC. When the motor drive device 1 is connected to the external AC power source AC as a household power source, a power source for other equipment, or the like, AC electric power is supplied from the external AC terminals 51 to the motor drive device 1, and is able to be stored in the electric storage device 3 as a DC power source. This process will be described later.

[0066] The third inverter 30 has DC terminals 31, AC terminals 32, and two-phase arms connected in parallel. Each arm has a pair of switching elements, such as IGBTs, connected in series, and a free-wheeling diode connected in parallel to each switching element. The DC terminals 31 of the third inverter 30 are connected to positive-side and negative-side leads of each arm, and are connected to the electric storage device 3 via the capacitor C2 and the third switch 35 described later. The AC terminals 32 of the third inverter 30 are connected to connection points between the pair of switching elements of each arm, and are connected to the transformer 53. The third inverter 30 and the transformer 53 can also be provided as three-phase in accordance with the number of phases of the second inverter 20 and the motor 5.

[0067] The first switch 15 is connected to the AC terminals 12 of the first inverter 10, and is selectively connected to either the first winding connection portion 5a of the motor 5 or the external AC terminals 51. That is, the first switch 15 can switch the AC terminals 12 of the first inverter 10 to be connected to either the first winding connection portion 5a or the external AC terminals 51.

[0068] The second switch 25 is connected to the AC terminals 22 of the second inverter 20, and is selectively connected to either the second winding connection portion 5b of the motor 5 or the transformer 53. That is, the second switch 25 can switch the AC terminals 22 of the second inverter 20 to be connected to either the second winding connection portion 5b or the transformer 53.

[0069] The third switch 35 is connected to the electric storage device 3, and is selectively connected to either the DC terminals 11 of the first inverter 10 and the DC terminals 21 of the second inverter 20, or the DC terminals 31 of the third inverter 30. That is, the third switch 35 can switch the electric storage device 3 to be connected to either the DC terminals 11 of the first inverter 10 and the DC terminals 21 of the second inverter 20, or the DC terminals 31 of the third inverter 30.

[0070] In addition to the above-described structure, the motor drive device 1 has a control device 7 (CPU). The control device 7 controls the operation of the motor drive device 1 as appropriate, and in particular, controls the switching of the first switch 15, the second switch 25, and the third switch 35, and the switching of the first inverter 10, the second inverter 20, and the third inverter 30. The control device 7 can be implemented by various processors (computers) and the like that operate in accordance with a predetermined program.

[0071] With respect to the motor drive device 1, the control device 7 can control in two modes, namely, 1) a drive mode in which the motor 5 is driven as when the vehicle is moving, and 2) an external AC charging mode in which power is transmitted between the electric storage device 3 and an external AC power source AC as when charging. Hereinafter, the drive mode will be described with reference to Figure 2 and Figure 3The modes are explained.

[0072] Figure 2 is a diagram showing the current flow in the drive mode. When driving the motor 5, the control device 7 controls the first switch 15, the second switch 25 and the third switch 35 as follows.

[0073] That is, the control device 7 controls the first switch 15 to connect the AC terminal 12 of the first inverter 10 with the first winding connection 5a. The control device 7 controls the second switch 25 to connect the AC terminal 22 of the second inverter 20 with the second winding connection 5b. Further, the control device 7 controls the third switch 35 to connect the electrical storage device 3 with the DC terminal 11 of the first inverter 10 and the DC terminal 21 of the second inverter 20.

[0074] By this control, the transmission path of the electric power which can be transmitted is set to the path from the electrical storage device 3 via the first inverter 10 and the second inverter 20 to the motor 5. As a result, the control device 7 can set a drive mode in which the electric power is transmitted along the solid arrows of Figure 2 and the motor 5 is driven using the first inverter 10 and the second inverter 20.

[0075] Figure 3 is a diagram showing the current flow in the external AC charging mode. When an external AC power source AC is connected to the external AC terminal 51, the control device 7 controls the first switch 15, the second switch 25 and the third switch 35 as follows.

[0076] That is, the control device 7 controls the first switch 15 to connect the AC terminal 12 of the first inverter 10 with the external AC terminal 51. The control device 7 controls the second switch 25 to connect the AC terminal 22 of the second inverter 20 with the transformer 53. Further, the control device 7 controls the third switch 35 to connect the electrical storage device 3 with the DC terminal 31 of the third inverter 30.

[0077] By this control, the transmission path of the electric power which can be transmitted is set to the path between the external AC power source AC and the electrical storage device 3 and via the first inverter 10, the second inverter 20 and the third inverter 30. As a result, the control device 7 can set an external AC charging mode in which the electric power is transmitted along the solid arrows of Figure 3 and the electric power transmission between the electrical storage device 3 and the external AC power source AC is performed using the first inverter 10, the second inverter 20 and the third inverter 30. This electric power transmission can be performed in both directions, i.e. from the electrical storage device 3 to the external AC power source AC and from the external AC power source AC to the electrical storage device 3, which is so-called bidirectional charging.

[0078] According to the motor drive device 1 of the present embodiment, when the motor 5 is driven, the first inverter 10 and the second inverter 20 can be used to drive the motor 5, and when the external alternating-current power supply AC is connected, the first inverter 10, the second inverter 20, and the third inverter 30 can be used to charge the electric storage device 3.

[0079] That is, in the driving mode and the external alternating-current charging mode, the first inverter 10 and the second inverter 20 are shared. Therefore, since the motor drive device 1 can share the driving circuit and the charging circuit, the number of electronic components used only for charging and the number of electronic components used only for driving are reduced, and the number of components can be reduced.

[0080] Since both the first inverter 10 and the second inverter 20 are used at the time of driving, the capacity can be halved compared to the case where one inverter is used. The first inverter 10 and the second inverter 20 can assume a plurality of functions of the insulation type AC charger (part of rectification / DC-DC conversion), and the capacity of the driving circuit for charging can be optimized.

[0081] Figure 4 is a circuit diagram of the motor drive device 1 of the second embodiment and a diagram showing the flow of current when the external direct-current power supply DC is connected in the circuit diagram. The motor drive device 1 of the present embodiment can not only be charged by the external alternating-current power supply AC but also be charged by the external direct-current power supply DC.

[0082] The motor drive device 1 of the present embodiment further has an external direct-current terminal 61 connected between the direct-current terminal 31 of the third inverter 30 and the third switch 35 via a fourth switch 45. The fourth switch 45 can be switched between an on state in which the external direct-current terminal 61 is connected to the direct-current terminal 31 of the third inverter 30 and the third switch 35 and an off state in which the connection between the external direct-current terminal 61 and the direct-current terminal 31 of the third inverter 30 and the third switch 35 is disconnected. In the present embodiment, the control device 7 can also control the fourth switch 45. When the external direct-current power supply DC is connected to the external direct-current terminal 61, the control device 7 sets the fourth switch 45 to the on state, and controls the second switch 25 and the third switch 35 as follows.

[0083] That is, the control device 7 controls the second switch 25 so that the alternating-current terminal 22 of the second inverter 20 is connected to the transformer 53. Further, the control device 7 controls the third switch 35 so that the electric storage device 3 is connected to the direct-current terminal 11 of the first inverter 10 and the direct-current terminal 21 of the second inverter 20. In addition, the control device 7 sets all the switching elements of the first inverter 10 to the off state.

[0084] By this control, the transmission path through which electric power can be transmitted is set to the path between the external DC power supply DC and the electric storage device 3 and via the second inverter 20 and the third inverter 30. As a result, the control device 7 can set a first external DC charging mode in which electric power is transmitted along the solid arrow of Figure 4 and the electric power transmission between the electric storage device 3 and the external DC power supply DC is performed using the second inverter 20, the transformer 53, and the third inverter 30. This electric power transmission can be performed in both directions, that is, from the electric storage device 3 to the external DC power supply DC and from the external DC power supply DC to the electric storage device 3, which is so-called bidirectional charging.

[0085] According to the motor drive device 1 of the present embodiment, when the external DC power supply DC is connected, the electric storage device 3 can be charged using the second inverter 20, the transformer 53, and the third inverter 30. The external DC power supply DC is, for example, a portable battery.

[0086] Figure 5 is a circuit diagram of the motor drive device 1 of the third embodiment and a diagram showing the current flow when the external DC power supply DC is connected in the circuit diagram. The basic structure of the present embodiment is the same as that of the second embodiment. However, unlike the second embodiment, when the external DC power supply DC is connected to the external DC terminal 61, the control device 7 sets the fourth switch 45 to the on state and controls the third switch 35 as follows.

[0087] That is, the control device 7 controls the third switch 35 so that the electric storage device 3 is connected to the DC terminal 31 of the third inverter 30. Further, the control device 7 sets all the switching elements of the third inverter 30 to the off state and transmits electric power to the electric storage device 3 without using the third inverter 30.

[0088] By this control, the transmission path through which electric power can be transmitted is set to the path between the external DC power supply DC and the electric storage device 3 and not via the third inverter 30. As a result, the control device 7 can set a second external DC charging mode in which electric power is transmitted along the solid arrow of Figure 5 and the electric power transmission between the electric storage device 3 and the external DC power supply DC is performed without using the third inverter 30. This electric power transmission can be performed in both directions, that is, from the electric storage device 3 to the external DC power supply DC and from the external DC power supply DC to the electric storage device 3, which is so-called bidirectional charging.

[0089] According to the motor drive device 1 of the present embodiment, when the external DC power supply DC is connected, the electric storage device 3 can be charged without using the third inverter 30. The external DC power supply DC is, for example, a quick charger.

[0090] Figure 6 is a circuit diagram of the motor drive device 1 of the fourth embodiment. The motor drive device 1 of the present embodiment has an auxiliary machine connection circuit 71 in addition to the structure of the above-described embodiments, the auxiliary machine connection circuit 71 being connected between the first inverter 10 and the second inverter 20 and the third switch 35 and performing power transmission with an auxiliary machine. The auxiliary machine includes, for example, a DC-DC converter 73 and an electric oil pump 75. The DC-DC converter 73 preferably constitutes the power conversion unit 8 together with the first inverter 10 and the second inverter 20.

[0091] In the present embodiment, the control device 7 is also capable of controlling the auxiliary machine connection circuit 71. The control device 7 stops the operation of the auxiliary machine connection circuit 71 when switching between the drive mode and the external AC charging mode.

[0092] By this control, the arc generated by the third switch 35 can be suppressed when switching between the drive mode and the external AC charging mode, thereby prolonging the life of the third switch 35.

[0093] Figure 7 is a circuit diagram of the motor drive device 1 of the fifth embodiment. The motor drive device 1 of the present embodiment is a modification of the motor drive device 1 of the fourth embodiment, the auxiliary machine connection circuit 71 being connected between the electric storage device 3 and the third switch 35 and performing power transmission with an auxiliary machine. According to this structure, the auxiliary machine can be continued to be used also when switching between the drive mode and the external AC charging mode.

[0094] The motor drive device 1 can be mounted on a vehicle having a driver operation portion (shift device, switch, button, touch panel, etc.) that switches the driving state according to the driver's operation. In this case, the motor 5 is a driving source of the vehicle, and the control device 7 is linked with the driver operation portion, thereby switching between the first switch 15, the second switch 25, and the third switch 35. According to this structure, the power supply to the motor 5 can be cut off in linkage with the driver operation portion, and thus the power supply to the motor 5 can be cut off at the time of parking.

[0095] The first switch 15 and the second switch 25 can be constituted by C-contact switches, for example. The C-contact switch is a switch in which, when one contact switch is in the connected state, the other contact switch is in the disconnected state, and when one contact switch is in the disconnected state, the other contact switch is in the connected state. According to this structure, the contact switches are not physically connected at the same time, and thus the charging current can be prevented from flowing to the motor 5.

[0096] Figure 8is a circuit diagram of the motor drive device 1 of the sixth embodiment and a diagram showing current flow when the non-contact charging device 81 is connected in the circuit diagram. The motor drive device 1 of the present embodiment is provided with the non-contact charging device 81 connected to the AC terminal 32 of the third inverter 30 in parallel with the transformer 53, in addition to the structure of the above-described embodiments. According to this structure, the third inverter 30 can be used as an inverter of the non-contact charging device 81, thereby preventing an increase in cost due to the addition of the non-contact charging function.

[0097] The above-described embodiments are illustrative of the ways in which the present application can be carried out and are not meant to limit the application in any way. Various modifications and substitutions can be made without departing from the spirit of the application.

[0098] In addition, at least the following matters are described in the present specification. Further, corresponding components and the like in the above-described embodiments are shown in parentheses, but the present application is not limited thereto.

[0099] (1) A motor drive device (motor drive device 1) comprising:

[0100] a power storage device (power storage device 3);

[0101] a motor (motor 5) having at least a first winding connection portion (first winding connection portion 5a) and a second winding connection portion (second winding connection portion 5b);

[0102] a first inverter (first inverter 10) having a DC terminal (DC terminal 11) and an AC terminal (AC terminal 12) for supplying electric power from the power storage device to the first winding connection portion;

[0103] a second inverter (second inverter 20) having a DC terminal (DC terminal 21) and an AC terminal (AC terminal 22) for supplying electric power from the power storage device to the second winding connection portion; and

[0104] an external AC terminal (external AC terminal 51) capable of transmitting electric power between the power storage device and an external AC power source,

[0105] wherein the motor drive device further comprises:

[0106] a third inverter (third inverter 30) having a DC terminal (DC terminal 31) and an AC terminal (AC terminal 32);

[0107] a transformer (transformer 53) connected to the AC terminal of the third inverter;

[0108] a first switch (first switch 15) capable of switching the AC terminal of the first inverter to a state of being connected to either of the first winding connection portion and the external AC terminal;

[0109] a second switch (second switch 25) capable of switching the AC terminal of the second inverter to a state of being connected to either of the second winding connection portion and the transformer; and

[0110] a third switch (third switch 35) capable of switching the electric storage device to a state of being connected to either of the DC terminal of the first inverter and the DC terminal of the second inverter and the DC terminal of the third inverter.

[0111] According to (1), the drive circuit and the charging circuit can be shared, so the number of electronic components used only for charging and electronic components used only for driving is reduced, and the number of components can be reduced. Since both the first inverter and the second inverter are used at the time of driving, the capacity can be halved compared to the case where one inverter is used. The first inverter and the second inverter can assume multiple functions (part of rectification / DC-DC conversion) of the insulated AC charger, and the capacity of the drive circuit used for charging can be optimized.

[0112] (2) The motor drive device according to (1), further comprising:

[0113] a control device (control device 7) that controls the first to third switches and the first to third inverters,

[0114] when the motor is driven, the control device

[0115] controls the first switch to connect the AC terminal of the first inverter to the first winding connection portion,

[0116] controls the second switch to connect the AC terminal of the second inverter to the second winding connection portion,

[0117] controls the third switch to connect the electric storage device to the DC terminal of the first inverter and the DC terminal of the second inverter, and

[0118] is set to a drive mode in which the first inverter and the second inverter are used to drive the motor,

[0119] when the external AC power source is connected to the external AC terminal, the control device

[0120] controls the first switch to connect the AC terminal of the first inverter to the external AC terminal,

[0121] the second inverter to the transformer,

[0122] the third inverter to the direct current terminal of the first inverter and the direct current terminal of the second inverter, and

[0123] an external alternating current charging mode in which the power transfer between the electric storage device and the external alternating current power source is performed using the first inverter, the second inverter, and the third inverter.

[0124] According to (2), when the motor is driven, the first inverter and the second inverter can be used to drive the motor, and when the external alternating current power source is connected, the first inverter, the second inverter, and the third inverter can be used to charge the electric storage device.

[0125] (3) The motor drive device according to (2), further comprising:

[0126] an external direct current terminal (external direct current terminal 61) connected between the direct current terminal of the third inverter and the third switch,

[0127] when an external direct current power source is connected to the external direct current terminal, the control device

[0128] the second inverter to the transformer,

[0129] the third inverter to the direct current terminal of the first inverter and the direct current terminal of the second inverter, and

[0130] a first external direct current charging mode in which the power transfer between the electric storage device and the external direct current power source is performed using the second inverter, the transformer, and the third inverter.

[0131] According to (3), when the external direct current power source is connected, the second inverter, the transformer, and the third inverter can be used to charge the electric storage device.

[0132] (4) The motor drive device according to (2), further comprising:

[0133] an external direct current terminal (external direct current terminal 61) connected between the direct current terminal of the third inverter and the third switch,

[0134] when an external direct current power source is connected to the external direct current terminal, the control device

[0135] the third inverter to the direct current terminal of the third inverter.

[0136] a second external DC charging mode in which power transmission is performed with the electrical storage device without using the third inverter.

[0137] According to (4), when the external DC power source is connected, the electrical storage device can be charged without using the third inverter.

[0138] (5) The motor drive device according to any one of (2) to (4), further comprising:

[0139] an auxiliary machine connection circuit (auxiliary machine connection circuit 71) connected between the first inverter and the second inverter and the third switch and performing power transmission with an auxiliary machine (DC-DC converter 73, electric oil pump 75),

[0140] the control device is capable of controlling the auxiliary machine connection circuit,

[0141] the control device stops the operation of the auxiliary machine connection circuit when switching between the drive mode and the external AC charging mode.

[0142] According to (5), when switching between the drive mode and the external AC charging mode, the arc generated by the third switch can be suppressed, thereby prolonging the life of the third switch.

[0143] (6) The motor drive device according to any one of (2) to (4), further comprising:

[0144] an auxiliary machine connection circuit (auxiliary machine connection circuit 71) connected between the electrical storage device and the third switch and performing power transmission with an auxiliary machine (DC-DC converter 73, electric oil pump 75).

[0145] According to (6), the auxiliary machine can also be continued to be used when switching between the drive mode and the external AC charging mode.

[0146] (7) The motor drive device according to any one of (2) to (6), wherein,

[0147] the motor drive device is mounted on a vehicle provided with a driver operation portion that switches a driving state according to an operation of a driver,

[0148] the motor is a driving source of the vehicle,

[0149] the control device is linked with the driver operation portion, thereby switching between the first switch, the second switch, and the third switch.

[0150] According to (7), the power supply to the motor can be cut off in conjunction with the driver operation section, so the power supply to the motor can be cut off at the time of parking.

[0151] (8) The motor drive device according to (7), wherein

[0152] The first switch and the second switch are constituted by a C-contact switch.

[0153] According to (8), the C-contact switch is not physically connected at the same time, so the charging current can be prevented from flowing to the motor.

[0154] (9) The motor drive device according to any one of (1) to (8), further comprising:

[0155] A non-contact charging device (non-contact charging device 81) is connected between the transformer and the AC terminal of the third inverter.

[0156] According to (9), the third inverter can be used as an inverter for a non-contact charging device, so the cost increase due to the addition of a non-contact charging function can be prevented.

Claims

1. A motor drive device comprising: Energy storage devices; A motor having at least a first winding connection portion and a second winding connection portion; A first inverter has DC terminals and AC terminals for supplying power from the energy storage device to the first winding connection. A second inverter, having DC and AC terminals, is used to supply power from the energy storage device to the second winding connection; and An external AC terminal is provided, which enables the transmission of power between the energy storage device and an external AC power source. The motor drive device further includes: The third inverter has both DC and AC terminals; A transformer connected to the AC terminal of the third inverter; A first switch is capable of switching the AC terminal of the first inverter to a state where it is connected to either the first winding connection or the external AC terminal. A second switch, capable of switching the AC terminals of the second inverter to a state where they are connected to either the second winding connection or the transformer; and A third switch is capable of switching the energy storage device to a state connected to any one of the DC terminals of the first inverter, the second inverter, and the third inverter.

2. The motor drive device according to claim 1, wherein, It also has: The control device controls the first to third switches and the first to third inverters. When the motor is driven, the control device Control the first switch to connect the AC terminal of the first inverter to the first winding connection portion. Control the second switch to connect the AC terminal of the second inverter to the second winding connection portion. Control the third switch to connect the energy storage device to the DC terminal of the first inverter and the DC terminal of the second inverter, and The drive mode is configured to use the first inverter and the second inverter to drive the motor. When the external AC power supply is connected to the external AC terminal, the control device Control the first switch to connect the AC terminal of the first inverter to the external AC terminal. Control the second switch to connect the AC terminal of the second inverter to the transformer. Control the third switch to connect the energy storage device to the DC terminal of the third inverter, and An external AC charging mode is configured to use the first inverter, the second inverter, and the third inverter to transmit power between the energy storage device and the external AC power source.

3. The motor drive device according to claim 2, wherein, It also has: An external DC terminal is connected between the DC terminal of the third inverter and the third switch. When an external DC power supply is connected to the external DC terminal, the control device Control the second switch to connect the AC terminal of the second inverter to the transformer. Control the third switch to connect the energy storage device to the DC terminal of the first inverter and the DC terminal of the second inverter, and This is configured as a first external DC charging mode that uses the second inverter, the transformer, and the third inverter to transmit power between the energy storage device and the external DC power source.

4. The motor drive device according to claim 2, wherein, It also has: An external DC terminal is connected between the DC terminal of the third inverter and the third switch. When an external DC power supply is connected to the external DC terminal, the control device Control the third switch to connect the energy storage device to the DC terminal of the third inverter, and This is configured as a second external DC charging mode that transmits power to the energy storage device without using the third inverter.

5. The motor drive device according to any one of claims 2 to 4, wherein, It also has: The auxiliary circuit is connected between the first inverter and the second inverter and the third switch, and transmits power to the auxiliary unit. The control device is capable of controlling the auxiliary machine connection circuit. The control device stops the operation of the auxiliary machine connection circuit when switching between the drive mode and the external AC charging mode.

6. The motor drive device according to any one of claims 2 to 4, wherein, It also has: The auxiliary machine connection circuit is connected between the energy storage device and the third switch, and transmits power to the auxiliary machine.

7. The motor drive device according to any one of claims 2 to 6, wherein, The motor drive unit is mounted on a vehicle equipped with a driver control unit, which switches driving modes according to the driver's input. The motor is the driving source of the vehicle. The control device is linked to the driver's operating unit, thereby switching between the first switch, the second switch, and the third switch.

8. The motor drive device according to claim 7, wherein, The first switch and the second switch are both composed of C-contact switches.

9. The motor drive device according to any one of claims 1 to 8, wherein, It also has: A contactless charging device is connected between the transformer and the AC terminals of the third inverter.

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