Motor control device and semiconductor unit

Abstract

Provided is a motor control device that prevents a motor from being unable to be driven even when a defect has occurred in an inverter that controls a battery or the motor current.　This motor control device (100) comprises: a plurality of semiconductor devices (UN) each having a semiconductor device (inverter circuit IV) that drives a motor (MT); and a battery (BP) that supplies direct current power to the semiconductor device (inverter circuit IV), wherein the semiconductor devices (inverter circuits IV) of each of the plurality of semiconductor units (UN) are electrically connected in parallel to the motor (MT).

Description

[Technical field]

[0001] The present disclosure relates to a motor control device, and more particularly to a motor control device with improved fault tolerance. [Background technology]

[0002] An inverter that drives a motor using a battery as a power source receives DC power from a battery pack consisting of multiple battery cells connected together and a battery consisting of multiple battery packs connected together, converts it into AC power, and supplies the AC power to the motor.

[0003] In today's battery-powered electric vehicles and the like, inverters are used not only to supply current from the battery to the motor, but also to control the charging of the battery with regenerative current from the motor, as disclosed in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-283678 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventionally, if a malfunction occurs in the inverter that controls the motor current, the charging and discharging of the motor cannot be controlled. For example, in an electric vehicle known as a battery electric vehicle (EV), if a malfunction occurs in the inverter, the vehicle may be completely unable to run, or if regenerative braking is in operation, braking may become less effective.

[0006] The present disclosure has been made to solve the problems described above, and aims to provide a motor control device that prevents the motor from becoming unable to be driven even if a malfunction occurs in the battery or the inverter that controls the motor current. [Means for solving the problem]

[0007] A motor control device according to the present disclosure includes a plurality of semiconductor units each having a semiconductor device that drives a motor and a battery that supplies DC power to the semiconductor device, and the semiconductor device of each of the plurality of semiconductor units is electrically connected in parallel to the motor. Each of the plurality of semiconductor units has a control device that controls the semiconductor device, the semiconductor device and the battery are provided integrally or in close contact with each other, the semiconductor device is an inverter circuit, the inverter circuit has a temperature sensor that measures a temperature of a switching element that constitutes the inverter circuit, the control device estimates a temperature of the battery based on the temperature of the switching element measured by the temperature sensor, and controls the switching element based on the temperature of the battery. do. Effect of the Invention

[0008] According to the motor control device of the present disclosure, the semiconductor devices of the multiple semiconductor units are electrically connected in parallel to the motor, so that even if a malfunction occurs in the battery or semiconductor device of one of the semiconductor units, it is possible to prevent the motor from being unable to be driven, thereby improving fault tolerance. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing a configuration of a motor control device according to a first embodiment. [Diagram 2] FIG. 11 is a perspective view showing a configuration of a battery pack of a semiconductor unit according to a second embodiment. [Diagram 3] FIG. 11 is a perspective view showing a configuration of a semiconductor unit according to a second embodiment. [Figure 4] 11 is a diagram showing an internal configuration of an inverter unit that constitutes a semiconductor unit according to a second embodiment. FIG. [Diagram 5] FIG. 11 is a diagram showing a configuration of a motor control device according to a third embodiment. [Figure 6] 11 is a flowchart showing autonomous control of a unit ECU in a motor control device according to a third embodiment. [Figure 7] FIG. 2 is a perspective view showing a schematic configuration of a semiconductor unit mounted on an electric vehicle. [Figure 8] FIG. 13 is a diagram showing the configuration of a motor control device according to a fifth embodiment. [Figure 9] FIG. 13 is a cross-sectional view showing a configuration of a semiconductor unit according to a sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] <Embodiment 1> Fig. 1 is a diagram showing the configuration of a motor control device 100 according to a first embodiment. As shown in Fig. 1, the motor control device 100 includes three semiconductor units UN each having a battery pack BP in which a plurality of battery cells BC are combined, and an inverter circuit IV which is a semiconductor device to which DC power is supplied from the battery pack BP, and the three semiconductor units UN drive one motor MT. Note that in reality, the number of battery cells BC constituting the battery pack BP is greater, and a battery is constituted by a plurality of battery packs BP connected in parallel, but for ease of illustration and explanation, the battery is constituted by one battery pack BP composed of five battery cells BC.

[0011] The semiconductor unit UN includes an IGBT (insulated gate bipolar transistor) 7a and a power supply line connected to a P terminal PT on the high potential side connected to the positive electrode of the battery pack BP and a power supply line connected to an N terminal NT on the low potential side connected to the negative electrode of the battery pack BP. The IGBT 10a is connected in series, the IGBT 7b and the IGBT 10b are connected in series, and the IGBT 7c and the IGBT 10c are connected in series. A smoothing capacitor SC is connected in parallel to the battery pack BP.

[0012] The connection node between IGBT7a and IGBT10a provides a U-phase output, the connection node between IGBT7b and IGBT10b provides a V-phase output, and the connection node between IGBT7c and IGBT10c provides a W-phase output, forming a three-phase AC inverter.

[0013] In addition, diodes 8a and 9a are connected in anti-parallel to IGBT7a and IGBT10a, diodes 8b and 9b are connected in anti-parallel to IGBT7b and IGBT10b, and diodes 8c and 9c are connected in anti-parallel to IGBT7c and IGBT10c.

[0014] The U-phase output, V-phase output, and W-phase output of each semiconductor unit UN are connected to the U-phase input, V-phase input, and W-phase input of the motor MT, respectively, and the motor MT is configured with three semiconductor units UN connected in parallel.

[0015] By adopting such a configuration, even if a malfunction occurs in the battery pack BP or the inverter circuit IV and the function of one of the semiconductor units UN is reduced, the other semiconductor units UN complement it, so that the motor function can be operated without being stopped. In particular, when it is adopted in an electric vehicle, since the function of the motor MT does not stop, it is possible to move the vehicle to a safe place. Note that, although FIG. 1 shows a configuration in which one motor MT is driven by three semiconductor units UN, the above-mentioned effect can be achieved by using two or more semiconductor units UN.

[0016] 1, when one motor MT is driven by three semiconductor units UN, if the maximum drive current of the motor MT is 600 A, each inverter circuit IV can have a maximum output current of 200 A. This allows the inverter circuit IV and the battery pack BP to be miniaturized, and each semiconductor unit UN can be made smaller.

[0017] <Embodiment 2> Fig. 2 is a perspective view showing the configuration of a battery pack BP of the semiconductor unit UN of the motor control device 100 shown in Fig. 1. As shown in Fig. 2, the battery pack BP is configured such that a plurality of battery cells BC are stacked, and each battery cell BC has a positive electrode PE and a negative electrode NE protruding from one side of the cell.

[0018] In the battery pack BP shown in Fig. 2, the negative electrode NE of the top battery cell BC and the positive electrode PE of the next battery cell BC are connected by a connection plate CB, and thereafter, the negative electrode NE of the top battery cell BC and the positive electrode PE of the lower battery cell BC are connected to each other by a connection plate CB, so that the top battery cell BC and the bottom battery cell BC are electrically connected in series. Note that in Fig. 2, the positive electrode PE of the top battery cell BC and the negative electrode NE of the bottom battery cell BC are not connected to anything, but this will be explained later.

[0019] A stack of multiple battery cells BC is housed in a resin case RC and configured as a single package.

[0020] FIG. 3 shows a battery pack BP shown in FIG. 2, which includes an inverter unit IVU, a smoothing capacitor SC, and a unit ECU (Electronic Control Unit) which is a control device for the inverter unit IVU. 1 shows a semiconductor unit UN equipped with a control unit (CU) 20.

[0021] 3, the semiconductor unit UN is mounted on the upper surface of the battery pack BP with an inverter unit IVU incorporating an inverter circuit IV, a smoothing capacitor SC, and a unit ECU 20, and capacitor terminals T1 and T2 protrude from the side surface of the smoothing capacitor SC. The capacitor terminal T1 is connected to the positive electrode PE of the uppermost battery cell BC by a connection plate CB1, and the capacitor terminal T2 is connected to the negative electrode NE of the lowermost battery cell BC by a connection plate CB2.

[0022] Capacitor terminals T1 and T2 also protrude from the side surface of smoothing capacitor SC on the inverter unit IVU side, and are connected to the P-terminal PT (FIG. 1) and N-terminal NT (FIG. 1) in inverter unit IVU, respectively.

[0023] A U-phase output terminal UT, a V-phase output terminal VT, and a W-phase output terminal WT protrude from the side surface of the inverter unit IVU opposite to the smoothing capacitor SC side.

[0024] The unit ECU 20 includes a control circuit that controls the inverter circuit IV. The inverter unit IVU, smoothing capacitor SC and unit ECU 20 are housed in a resin case RC1 to form a single package, and are in close contact with the battery pack BP.

[0025] Therefore, the arrangement space can be reduced compared to the case where the battery and the inverter circuit are arranged separately. That is, in a conventional electric vehicle, for example, when the maximum drive current of the motor is 600A, a battery with a capacity of 600A and an inverter circuit with a rated output of 600A are arranged separately, and in particular, the inverter circuit is arranged near the motor. Therefore, an arrangement space for the inverter circuit, which requires a large volume, is provided above the motor. Recently, vehicles in which the motor is arranged on the axle have been developed, and it has become difficult to provide an arrangement space for the inverter circuit, which requires a large volume, above the motor. However, when one motor is driven using three semiconductor units UN as shown in FIG. 3, by arranging the three semiconductor units UN on the chassis of the vehicle, it is no longer necessary to provide a large space for the inverter circuit above the motor, and the arrangement space can be reduced. Therefore, it is possible to secure a crash zone in the event of an accident, a space under the bonnet, and a space for loading luggage.

[0026] Fig. 4 is a diagram showing the internal configuration of the inverter unit IVU shown in Fig. 3. As shown in Fig. 4, the inverter unit IVU includes a voltage sensor VS connected between the P-terminal PT and the N-terminal NT, a current sensor CS inserted in the main power supply line connected to the P-terminal PT, and a temperature sensor TS provided, for example, near the IGBT 10c.

[0027] The detection outputs of the voltage sensor VS, the current sensor CS and the temperature sensor TS are input to the unit ECU 20.

[0028] The voltage sensor VS detects the voltage that is the output voltage of the battery pack BP and the input voltage of the inverter circuit IV, and the unit ECU 20 detects the state of charge of the battery pack BP based on the detected voltage and controls the main current of the inverter circuit IV.

[0029] By providing the voltage sensor VS, the battery can be prevented from being overcharged by a battery controller provided in the unit ECU 20 (not shown), and the cell controllers provided corresponding to each of the battery cells BC can discharge the battery cells with the most charged capacity first, thereby making it possible to consume the battery evenly. Also, the charging time can be shortened by preferentially increasing the charging current for cells with a low charged capacity during charging. The charging and discharging control of the battery pack BP can use known techniques such as those disclosed in Japanese Patent Laid-Open Publication No. 2000-299939.

[0030] Furthermore, by providing the temperature sensor TS, the unit ECU 20 estimates the temperature of the battery pack BP from the difference between the temperature of the IGBT during operation detected by the temperature sensor TS and the amount of heat generated from the power loss of the IGBT predicted in advance. Then, based on the estimated temperature, the main current of the inverter circuit IV can be controlled, and appropriate charge / discharge control according to the battery temperature can be performed. Furthermore, since there is no need to provide a temperature sensor in the battery pack BP, the battery pack BP can be made smaller and the manufacturing cost can be reduced.

[0031] For example, when the battery pack BP and the inverter unit IVU are in close contact with each other, the temperature change of the IGBT can be calculated as Rth × LW from the thermal resistance Rth (℃ / W) of the IGBT chip and the power loss LW (W) of the IGBT, and the temperature of the battery pack BP can be expressed as T-Rth × LW using the detected IGBT temperature T (℃).

[0032] By implementing such charge / discharge control, it is possible to prevent overheating and overloading at low temperatures and low charge / discharge capacity for each battery pack, suppress deterioration of the battery pack, and prevent the vehicle from stopping due to battery failure in an electric vehicle. Note that, although an example of estimating the temperature of the battery pack BP from the temperature during operation of the IGBT has been described above, the charge / discharge control based on the temperature detection of the battery pack can use known techniques such as those disclosed in Japanese Patent Laid-Open Publication No. 2000-299939.

[0033] 4 is shown as a sensor independent of the IGBT, such as a thermistor, but a temperature sensing diode with a cathode connected to the emitter of the IGBT and an anode connected to a temperature sensing terminal can also be used. In this case, the temperature sensing terminal is connected to a current detection circuit provided in the unit ECU 20, and the temperature of the IGBT is calculated from the detected current.

[0034] <Embodiment 3> FIG. 5 is a diagram showing a configuration in which three inverter units IVU shown in FIG. 4 are electrically connected in parallel to a motor (not shown), and each unit ECU 20 is connected to a motor ECU 30 which is a higher-level control device.

[0035] The motor ECU 30 (hereinafter, sometimes referred to as "MCU") controls the on-off time (duty) of the switching elements so as to achieve the goals of motor control and battery charge / discharge control. That is, the MCU inputs the duty and the reference voltage to each unit ECU 20.

[0036] The unit ECU 20, to which the duty and the reference voltage are input, compares the voltage of the battery pack BP detected by the voltage sensor VS with the reference voltage, and when the actual voltage of the battery pack BP is higher than the reference voltage, for example, in the case where the duty is a control to instruct discharging, i.e., control to turn on the switching element, the duty is changed to lengthen the on-time to discharge more.In the case where the duty is a control to instruct charging, the duty is changed to shorten the on-time to lengthen the charging path via the diode element.

[0037] By controlling in this manner, the control state can be changed independently for each inverter circuit IV, and even if a malfunction occurs in any of the semiconductor units UN, it is possible to deal with the malfunction for each semiconductor unit UN.

[0038] Fig. 6 is a flowchart showing the autonomous control of the unit ECU 20 by the motor ECU 30. As shown in Fig. 6, the motor ECU 30 sets a target current to be input to the motor (step S1), and thereafter continuously checks whether there is a difference between the target current and the actual current fed back from the unit ECU 20 (step S2).

[0039] In step S2, if there is a difference between the target current and the actual current (if Yes), a control duty for compensating for the difference is output to each unit ECU 20. If the target current and the actual current match, a control duty for specifying the target current is output, and the process of setting the target current in step S1 is repeated.

[0040] The unit ECU 20 receives the control duty and the reference voltage from the MCU (step S11), and compares the voltage of the battery pack BP with the reference voltage (step S12). If the voltage of the battery pack BP is higher than the reference voltage (Yes), the process proceeds to step S13; if the voltage is lower than the reference voltage (No), the process proceeds to step S14.

[0041] In step S13, the control duty is increased by a preset value so as to lengthen the ON time in order to increase the amount of discharge from the battery pack BP, and the process proceeds to step S17, whereby the voltage of the battery pack BP can be prevented from becoming too high.

[0042] In step S14, the voltage of the battery pack BP is compared with a reference voltage, and if the voltage of the battery pack BP is lower than the reference voltage (Yes), the process proceeds to step S15, and if it is the reference voltage (No), the process proceeds to step S16.

[0043] In step S15, the control duty is subtracted by a preset value so as to shorten the ON time in order to reduce the amount of discharge from the battery pack BP, and the process proceeds to step S17.

[0044] In step S16, a control duty designated by the MCU is set, and the process proceeds to step S17.

[0045] In step S17, a control duty is applied to each switching element of the inverter circuit IV to control it.

[0046] As a result of the control duty being changed by the unit ECU 20, the actual current flowing through the motor approaches the target current, and the charging and discharging control of the battery is also performed appropriately. The actual current flowing through the motor is detected by a current sensor (not shown) and fed back to the motor ECU 30.

[0047] The above-described control flow shows a control flow based on the voltage of the battery pack BP detected by the voltage sensor VS, but similar control is also possible using an estimated value of the temperature of the battery pack BP based on the temperature of the switching element, i.e., the IGBT, detected by the temperature sensor TS.

[0048] In addition, the above-mentioned control flow shows an example of changing the control duty of the switching element, but a method of increasing or decreasing the power loss of the switching element by changing the drive frequency of the switching element, i.e., the switching speed, can also be adopted. That is, the power loss of the switching element is reduced by lowering the drive frequency and increased by raising the drive frequency. Instead of lengthening the on-time of the switching element, the drive frequency of the switching element is raised to increase the power loss and control so that more is discharged from the battery pack BP. This makes it possible to prevent the voltage of the battery pack BP from becoming too high.

[0049] In addition, if the battery pack BP and the inverter unit IVU have a common cooling mechanism, it is also possible to control the cooling capacity of the cooling mechanism, for example, switching of the refrigerant flow path or switching of the refrigerant flow rate, based on the temperature of the IGBT and an estimated value of the temperature of the battery pack BP based on that temperature.

[0050] <Fourth embodiment> FIG. 7 is a perspective view showing a schematic configuration when the semiconductor unit UN shown in FIG. 3 is mounted on an electric vehicle, in which three semiconductor units UN are mounted on a chassis CC, and U-phase wiring UL, V-phase wiring VL and W-phase wiring WL from the three semiconductor units UN are connected to a motor MT mounted on an axle FAX of the front wheels FW.

[0051] By mounting the three semiconductor units UN on the chassis CC in this way, it is no longer necessary to provide space above the motor MT for the inverter circuit, which requires a large volume of space, making it possible to secure a crush zone in the event of an accident, space under the bonnet, and space for luggage.

[0052] In addition, in FIG. 7, an example in which the motor MT is mounted on the axle FAX of the front wheels FW is shown, but it can also be mounted on the axle RAX of the rear wheels RW, or on both the axle FAX of the front wheels FW and the axle RAX of the rear wheels RW. This makes it possible to accommodate rear-wheel drive vehicles and four-wheel drive vehicles. It is also possible to use an infoil motor with the motor built into the wheel (infoil). In this case, the crush zone in the event of an accident, the space under the bonnet, and the loading space for luggage can be further expanded.

[0053] <Fifth Preferred Embodiment> FIG. 8 is a diagram showing the configuration of a motor control device 100A according to a fifth embodiment. Note that FIG. 8 shows the configuration of the motor control device 100A described with reference to FIG. 0 and The same components are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0054] 8, in the motor control device 100A, a relay switch SW is inserted in U-phase wiring UL, V-phase wiring VL and W-phase wiring WL which respectively connect the U-phase output, V-phase output and W-phase output of the semiconductor unit UN to the U-phase input, V-phase input and W-phase input of the motor MT. The relay switch SW can be a semiconductor switching element or a mechanical switch.

[0055] By adopting such a configuration, if a malfunction occurs in the battery pack BP or inverter circuit IV of any of the semiconductor units UN, the relay switch SW connected to that semiconductor unit UN can be cut off (opened), making it possible to drive the motor MT using the remaining semiconductor units UN, thereby configuring a system with improved fault tolerance.

[0056] In addition, even if a malfunction occurs in any of the semiconductor units UN, there are cases where the relay switch SW connected to the semiconductor unit UN is not cut off. That is, as described in the first embodiment, when the maximum drive current of the motor MT is 600 A, each inverter circuit IV can have a maximum output current of 200 A. Among these, when a malfunction occurs in the inverter circuit IV and the output current can only be up to 100 A, the semiconductor unit UN having the inverter circuit IV is not cut off by the relay switch SW and is used as a semiconductor unit UN that outputs 100 A. As a result, although the vehicle cannot reach its maximum speed, it can maintain a speed that does not interfere with normal running. In addition, each semiconductor unit UN is configured to be able to output the maximum drive voltage of the motor MT, and for example, even if two semiconductor units UN are malfunctioning, the motor MT can be driven by only the remaining one semiconductor unit UN to run the vehicle.

[0057] In addition, the number of semiconductor units UN is not limited to three; from the viewpoint of obtaining a fault-tolerant system, a minimum of two is sufficient, and by using three or more units, the maximum output current per unit can be further reduced, resulting in a more robust fault-tolerant system.

[0058] The level to which the output current must drop before the relay switch SW is shut off is preset in the motor ECU, and the motor ECU can control the relay switch SW at its discretion.

[0059] <Sixth embodiment> The semiconductor unit UN shown in Figure 3 has a configuration in which an inverter unit IVU and a smoothing capacitor SC are mounted on a battery pack BP. The battery pack BP, the inverter unit IVU and the smoothing capacitor SC are each provided separately and then combined, but it is also possible to provide the battery, the inverter and the smoothing capacitor as an integrated unit.

[0060] 9 is a cross-sectional view showing a configuration of a semiconductor unit 10 according to a sixth embodiment. The semiconductor unit 10 has a semiconductor device 12. The semiconductor device 12 is an IGBT having an emitter formed on an upper surface and a collector formed on a lower surface. A first electrode 16 is electrically connected to the upper surface of the semiconductor device 12 via solder 14. The first electrode 16 functions as an emitter electrode.

[0061] A first internal electrode 18 is electrically connected to the bottom surface of the semiconductor device 12. The first internal electrode 18 has a plurality of first comb teeth 18a and a first connecting portion 18b connecting the plurality of first comb teeth 18a. The comb teeth of the plurality of first comb teeth 18a extend in parallel with each other. One of the comb teeth of the plurality of first comb teeth is in surface contact with the bottom surface of the semiconductor device 12.

[0062] The second electrode 17 is electrically connected to the first internal electrode 18. The second electrode 17 functions as a collector electrode. A second internal electrode 22 is formed at a position facing the first internal electrode 18. The second internal electrode 22 has a plurality of second comb teeth 22a and a second connecting portion 22b connecting the plurality of second comb teeth 22a. The comb teeth of the plurality of second comb teeth 22a extend in parallel with each other. The plurality of second comb teeth 22a do not contact the plurality of first comb teeth 18a but advance between the plurality of first comb teeth 18a. In other words, the plurality of first comb teeth 18a and the plurality of second comb teeth 22a are arranged to mesh with each other without contacting each other.

[0063] A space between the upper first comb teeth 18a and the upper second comb teeth 22a on the semiconductor device 12 side among the plurality of first comb teeth 18a and the plurality of second comb teeth 22a is filled with a dielectric 24. The dielectric 24 is made of ceramic. This forms a capacitor having the dielectric 24, the first comb teeth 18a, and the second comb teeth 22a, and using the first comb teeth 18a and the second comb teeth 22a as electrodes. The dielectric 24 has a recess 24a.

[0064] The gap between the lower first comb teeth 18a and the lower second comb teeth 22a, which are on the opposite side to the semiconductor device 12, is filled with a solid electrolyte 25. The solid electrolyte 25 is made of ceramic oxide. The electrode assembly 10 has a first comb-tooth portion 18a and a plurality of second comb-tooth portions 22a, and a battery is formed with the first comb-tooth portion 18a and the second comb-tooth portion 22a as electrodes.

[0065] The second internal electrode 22 is electrically connected to the lower surface of the first electrode 16. Specifically, one of the multiple second comb teeth 22a is electrically connected to the lower surface of the first electrode 16 via solder 26. A resin 30 is formed to cover the semiconductor device 12, the first internal electrode 18, and the second internal electrode 22, and to expose a part of the first electrode 16, a part of the second electrode 17, and a part of the lower dielectric 24 to the outside. The resin 30 is formed by a transfer molding method. The recess 24a described above is formed in a portion in contact with the resin 30, and therefore the recess 24a is filled with the resin 30.

[0066] The semiconductor unit 10 shown in FIG. 9 is configured such that a capacitor is formed on the top of a battery, and the battery and the capacitor are connected in parallel to the semiconductor device 12.

[0067] Here, although not shown, the semiconductor device 12 can be configured as, for example, a one-phase inverter circuit in which diodes 8a and 9a are connected in anti-parallel to IGBT 7a and IGBT 10a, which are connected in series in the inverter circuit IV shown in FIG. 1, and the semiconductor unit 10 can be configured as a one-phase inverter circuit, a battery, and a capacitor connected in parallel.

[0068] By connecting three one-phase inverter circuits in parallel, a three-phase inverter circuit IV shown in FIG. 1 can be obtained.

[0069] As shown in Fig. 9, by configuring the battery so that the capacitor is integrally formed on top of it, it can handle sudden charging. That is, since the charging current causes the voltage to rise due to the relationship of resistance x current due to the internal resistance, if an overcurrent is suddenly passed through a high resistance part, it will cause an overvoltage. Therefore, when charging, the capacitor with low internal resistance, which is also the smoothing capacitor, is charged first, and that current is passed through the battery, making it possible to handle large currents.

[0070] Although the present disclosure has been described in detail, the above description is illustrative in all respects and does not limit the present disclosure. It is understood that countless variations not illustrated can be assumed without departing from the scope of the present disclosure.

[0071] In addition, within the scope of the present disclosure, it is possible to freely combine the respective embodiments, and to appropriately modify or omit the respective embodiments.

Claims

1. A semiconductor device that drives a motor; a battery for supplying DC power to the semiconductor device; the semiconductor devices of the plurality of semiconductor units are electrically connected in parallel to the motor; Each of the plurality of semiconductor units has a control device that controls the semiconductor device, The semiconductor device and the battery are provided integrally or in close contact with each other, The semiconductor device is an inverter circuit, The inverter circuit includes: A temperature sensor for measuring the temperature of a switching element constituting the inverter circuit is provided. The control device includes: A motor control device that estimates a temperature of the battery based on the temperature of the switching element measured by the temperature sensor, and controls the switching element based on the temperature of the battery.

2. 2. The motor control device according to claim 1, wherein the temperature of the battery is estimated by calculating a temperature change of the switching element by multiplying the thermal resistance of the switching element by a power loss of the switching element, and subtracting the temperature change from the temperature of the switching element.

3. The semiconductor device has a voltage sensor that measures an output voltage of the battery, The control device includes:

2. The motor control device according to claim 1, further comprising: a switching element constituting the inverter circuit, the switching element being controlled based on the output voltage of the battery measured by the voltage sensor.

4. The motor is a motor for driving a vehicle, The motor control device according to claim 1 , wherein the plurality of semiconductor units are mounted on a chassis of the vehicle.

5. The motor is The motor control device according to claim 4 , which is mounted on at least one of the axles of the front and rear wheels of the vehicle, or in the wheels of the front and rear wheels.

6. The motor control device according to claim 1 , further comprising a switch for individually cutting off electrical connection between the semiconductor device of each of the plurality of semiconductor units and the motor.

7. A semiconductor device; a battery configured by connecting a plurality of battery cells in series and supplying DC power to the semiconductor device; A semiconductor unit in which the semiconductor device is mounted on the battery.

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