JP4948329B2 - Motor drive device and control method of motor drive device - Google Patents

Description

  The present invention relates to a motor drive device and a motor drive device control method, and more particularly to a motor drive device and a motor drive device control method in which a voltage applied to an inverter for driving a motor is variable by a voltage converter.

  In recent years, hybrid vehicles using a DC power source, an inverter, and a motor driven by the inverter as a power source have become widespread as environmentally friendly vehicles in addition to conventional engines.

  In order to rotate the motor at high speed, it is necessary to supply a power supply voltage higher than the counter electromotive force generated by the motor to the inverter of the motor. Therefore, a high-voltage battery is usually mounted to supply a high power supply voltage. However, in order to improve efficiency, some hybrid vehicles having such a configuration are equipped with a boost converter that boosts the voltage of the battery and supplies it to the inverter without increasing the voltage of the battery that is the DC power supply. The step-up converter supplies a high voltage exceeding the counter electromotive voltage to an inverter that drives the motor when the motor rotates at high speed when the counter electromotive voltage increases.

Japanese Patent Laying-Open No. 2006-246653 (Patent Document 1) discloses that at the time of overvoltage recovery of the boost converter, the operation of the boost converter is permitted after the boost voltage becomes lower than the component breakdown voltage on the low voltage device side of the boost converter.
JP 2006-246653 A

  However, the component withstand voltage changes depending on the state of the component (for example, characteristics such as the temperature of the component itself and the environment in which the component is placed). Therefore, it is preferable from the viewpoint of component protection to permit the operation of the boost converter in accordance with the worst state, that is, the state where the component breakdown voltage is the lowest, but the recovery of the boost converter operation is delayed in time. End up.

  For this reason, it is desirable to change the permission voltage when returning the operation of the boost converter from the overvoltage, but the technique disclosed in JP-A-2006-246653 still has room for improvement in this respect.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a motor drive device and a motor drive device control method capable of protecting parts and quickly returning to operation.

  In summary, the present invention provides a motor drive device, a motor for driving a wheel, an inverter for driving the motor, a power storage device, and a voltage of the power storage device is boosted to supply a first voltage to the inverter. A voltage converter that detects a first voltage supplied from the voltage converter to the inverter, a state detection sensor that detects a value representing the state of the motor drive device, and an inverter and a voltage according to the output of the voltage sensor And a control device for controlling the converter. The control device prohibits the operation of the voltage converter when the first voltage exceeds the first threshold voltage, and then the first voltage drops below the second threshold voltage lower than the first threshold voltage. When the operation of the voltage converter is canceled, the control device changes the second threshold voltage according to the output of the state detection sensor.

Preferably, the state detection sensor includes a sensor that detects atmospheric pressure.
Preferably, the state detection sensor includes a sensor that detects temperature.

  Preferably, the control device changes the target voltage of the voltage converter according to the output of the state detection sensor. When the prohibition on the operation of the voltage converter is canceled, the target voltage and the second threshold voltage are set to the same value.

  According to another aspect of the present invention, a motor for driving a wheel, an inverter for driving the motor, a power storage device, a voltage converter for boosting a voltage of the power storage device and supplying a first voltage to the inverter, A method for controlling a motor drive device, comprising: a voltage sensor that detects a first voltage supplied from a voltage converter to an inverter; and a state detection sensor that detects a value representing a state of the motor drive device. When the voltage exceeds the first threshold voltage, the step of prohibiting the operation of the voltage converter and the first voltage is lower than the first threshold voltage after the first voltage exceeds the first threshold voltage A step of releasing the prohibition of the operation on the voltage converter when the voltage falls below the second threshold voltage, and a step of changing the second threshold voltage according to the output of the state detection sensor.

Preferably, the state detection sensor includes a sensor that detects atmospheric pressure.
Preferably, the state detection sensor includes a sensor that detects temperature.

  Preferably, the control method changes the target voltage of the voltage converter according to the output of the state detection sensor and sets the target voltage and the second threshold voltage to the same value when the prohibition of the operation on the voltage converter is canceled. The method further includes a step.

  According to the present invention, it is possible to achieve both protection of components and quick operation recovery of the boost converter.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a diagram showing a main configuration of a vehicle 100 according to an embodiment of the present invention. The vehicle 100 is a hybrid vehicle that uses both a motor and an engine for driving the vehicle, but the present invention uses a power supplied from a converter to drive a motor with an inverter and travels with the driving force of the motor. Any vehicle can be applied.

  Referring to FIG. 1, vehicle 100 includes a battery B, a connection unit 40, a boost converter 12, smoothing capacitors C <b> 1 and C <b> 2, a discharge resistor R <b> 2, voltage sensors 13 and 21, and a load circuit 23. , Engine 4, motor generators MG <b> 1 and MG <b> 2, power split mechanism 3, wheels 2, and control device 30.

  Vehicle 100 further includes power supply lines PL1 and PL2, ground line SL, voltage sensor 10 for detecting voltage VB between terminals of battery B, and current sensor 11 for detecting current IB flowing through battery B. As the battery B, for example, a secondary battery such as a lead storage battery, a nickel metal hydride battery, or a lithium ion battery can be used.

  Connection unit 40 includes a system main relay SMR3 connected between the negative electrode of battery B and ground line SL, a system main relay SMR2 connected between the positive electrode of battery B and power supply line PL1, and a system main relay. It includes a resistor R1 and a system main relay SMR1 connected in series connected in parallel with SMR2. System main relays SMR1-SMR3 are controlled to be in a conductive / non-conductive state in accordance with control signals CONT1-CONT3 supplied from control device 30, respectively.

  Capacitor C1 smoothes the voltage across terminals of battery B when system main relays SMR1 to SMR3 are on. Capacitor C1 is connected between power supply line PL1 and ground line SL. An electric air conditioner 42 that is an electric load circuit and a DC / DC converter 44 are connected in parallel between the power supply line PL1 and the ground line SL. The DC / DC converter 44 charges the auxiliary battery 46 or supplies power to an auxiliary load (not shown).

  The voltage sensor 21 detects the voltage VL across the capacitor C1 and outputs it to the control device 30. Boost converter 12 boosts the voltage across terminals of capacitor C1. Capacitor C2 smoothes the voltage boosted by boost converter 12. The voltage sensor 13 detects the inter-terminal voltage VH of the smoothing capacitor C <b> 2 and outputs it to the control device 30. The discharge resistor R2 is inserted to ensure that the voltage VH is reduced to zero after the system is stopped.

  Load circuit 23 includes inverters 14 and 22. Note that the withstand voltage (for example, 600 V) of the electric air conditioner 42 and the DC / DC converter 44 that are electric loads is lower than the withstand voltage (for example, 900 V) of the inverters 14 and 22 of the load circuit 23. Inverter 14 converts the DC voltage applied from boost converter 12 into a three-phase AC and outputs the same to motor generator MG1.

  Power split device 3 is a mechanism that is coupled to engine 4 and motor generators MG1 and MG2 and distributes power between them. For example, as the power split mechanism, a planetary gear mechanism having three rotating shafts of a sun gear, a planetary carrier, and a ring gear can be used. These three rotation shafts are connected to the rotation shafts of engine 4 and motor generators MG1, MG2, respectively.

  The rotating shaft of motor generator MG2 is coupled to wheel 2 by a reduction gear and a differential gear (not shown). Further, a reduction gear for the rotation shaft of motor generator MG2 may be further incorporated in power split device 3. Moreover, you may incorporate the transmission comprised so that switching of the reduction ratio of this reduction gear was possible.

  Boost converter 12 is connected in parallel to reactor L1 having one end connected to power supply line PL1, IGBT elements Q1 and Q2 connected in series between power supply line PL2 and ground line SL, and IGBT elements Q1 and Q2. And diodes D1 and D2 connected to each other.

  Reactor L1 has the other end connected to the emitter of IGBT element Q1 and the collector of IGBT element Q2. The cathode of diode D1 is connected to the collector of IGBT element Q1, and the anode of diode D1 is connected to the emitter of IGBT element Q1. The cathode of diode D2 is connected to the collector of IGBT element Q2, and the anode of diode D2 is connected to the emitter of IGBT element Q2.

  Inverter 14 receives the boosted voltage from boost converter 12 and drives motor generator MG1 to start engine 4, for example. Inverter 14 returns the electric power generated by motor generator MG 1 by the power transmitted from engine 4 to boost converter 12. At this time, boost converter 12 is controlled by control device 30 to operate as a step-down circuit.

  Inverter 14 includes a U-phase arm 15, a V-phase arm 16, and a W-phase arm 17. U-phase arm 15, V-phase arm 16, and W-phase arm 17 are connected in parallel between power supply line PL2 and ground line SL.

  U-phase arm 15 includes IGBT elements Q3 and Q4 connected in series between power supply line PL2 and ground line SL, and diodes D3 and D4 connected in parallel with IGBT elements Q3 and Q4, respectively. The cathode of diode D3 is connected to the collector of IGBT element Q3, and the anode of diode D3 is connected to the emitter of IGBT element Q3. The cathode of diode D4 is connected to the collector of IGBT element Q4, and the anode of diode D4 is connected to the emitter of IGBT element Q4.

  V-phase arm 16 includes IGBT elements Q5 and Q6 connected in series between power supply line PL2 and ground line SL, and diodes D5 and D6 connected in parallel with IGBT elements Q5 and Q6, respectively. The cathode of diode D5 is connected to the collector of IGBT element Q5, and the anode of diode D5 is connected to the emitter of IGBT element Q5. The cathode of diode D6 is connected to the collector of IGBT element Q6, and the anode of diode D6 is connected to the emitter of IGBT element Q6.

  W-phase arm 17 includes IGBT elements Q7 and Q8 connected in series between power supply line PL2 and ground line SL, and diodes D7 and D8 connected in parallel with IGBT elements Q7 and Q8, respectively. The cathode of diode D7 is connected to the collector of IGBT element Q7, and the anode of diode D7 is connected to the emitter of IGBT element Q7. The cathode of diode D8 is connected to the collector of IGBT element Q8, and the anode of diode D8 is connected to the emitter of IGBT element Q8.

  The intermediate point of each phase arm is connected to one end of each phase coil of motor generator MG1. That is, motor generator MG1 is a three-phase permanent magnet synchronous motor, and one end of each of three coils of U, V, and W phases is connected to the midpoint. The other end of the U-phase coil is connected to the connection node of IGBT elements Q3 and Q4. The other end of the V-phase coil is connected to a connection node of IGBT elements Q5 and Q6. The other end of the W-phase coil is connected to a connection node of IGBT elements Q7 and Q8.

  Other power switching elements such as power MOSFETs may be used in place of the above IGBT elements Q1 to Q8.

  Current sensor 24 detects the current flowing through motor generator MG1 as motor current value MCRT1, and outputs motor current value MCRT1 to control device 30.

  Inverter 22 is connected to power supply line PL2 and ground line SL. Inverter 22 converts the DC voltage output from boost converter 12 into a three-phase AC and outputs the same to motor generator MG2 driving wheel 2. Inverter 22 returns the electric power generated in motor generator MG2 to boost converter 12 along with regenerative braking. At this time, boost converter 12 is controlled by control device 30 to operate as a step-down circuit. Although the internal configuration of inverter 22 is not shown, it is similar to inverter 14, and detailed description will not be repeated.

  Control device 30 receives torque command values TR1 and TR2, motor rotation speeds MRN1 and MRN2, voltages VB and VH, current IB values, motor current values MCRT1 and MCRT2, and a start instruction IGON. Control device 30 then outputs a signal PWC that gives an instruction including a boost instruction, a step-down instruction, an operation prohibition, and the like to boost converter 12.

  Furthermore, control device 30 outputs signal PWM1 that gives an instruction including a drive instruction, a regeneration instruction, an operation prohibition instruction, and the like to inverter 14. The drive instruction is an instruction to convert the DC voltage, which is the output of boost converter 12, into an AC voltage for driving motor generator MG1. The regeneration instruction is an instruction for converting the AC voltage generated by motor generator MG1 into a DC voltage and returning it to the boost converter 12 side.

  Similarly, control device 30 outputs signal PWM <b> 2 that gives an instruction including a drive instruction, a regeneration instruction, an operation prohibition instruction, and the like to inverter 22. The drive instruction is an instruction to convert the DC voltage that is the output of boost converter 12 into an AC voltage for driving motor generator MG2. The regeneration instruction is an instruction for converting the AC voltage generated by motor generator MG2 into a DC voltage and returning it to the boost converter 12 side.

  FIG. 2 is a functional block diagram of the control device 30 of FIG. The control device 30 can be realized by software or hardware.

  Referring to FIGS. 1 and 2, control device 30 includes a hybrid control unit 31 and a motor generator control unit 32.

  The hybrid controller 31 receives the accelerator opening Acc from the accelerator position sensor 26 that detects the position of the accelerator pedal, the wheel speed Nw proportional to the vehicle speed from the vehicle speed sensor 28, and the coolant temperature Tw from the water temperature sensor 27. The atmospheric pressure P is received from the atmospheric pressure sensor, and the signal VH is received from the voltage sensor 13.

  The hybrid control unit 31 calculates the driver's required output based on the accelerator opening Acc, the wheel speed Nw, and the outputs of various other sensors, and the battery sent from the battery monitoring unit that monitors the battery B (not shown). The total output is calculated in consideration of the state of charge SOC. Hybrid control unit 31 calculates the distribution of the driving force to engine 4 and motor generators MG1 and MG2 while taking into account the brake request, command GI for driving motor generator MG1, and command MI for driving motor generator MG2. Is output.

  Hybrid control unit 31 determines a boost target value in accordance with the higher rotational speed of motor generators MG1 and MG2, and outputs command CI for driving boost converter 12. When a voltage exceeding the higher back electromotive voltage can be generated, the hybrid control unit 31 sets the boost target value higher than the back electromotive voltage. If the boost voltage upper limit is lower than the back electromotive voltage, the hybrid control unit 31 The target value is set to the boost voltage upper limit value and the motor generator is caused to execute field weakening control so that the back electromotive voltage does not exceed the boost voltage.

  While issuing a drive command, the hybrid control unit 31 converts the signal VH sent from the voltage sensor 13 into a digital value at regular intervals using the A / D converter 34 and holds it in the register 35. Then, by monitoring the digital value, operation inhibition signals CSDN, MSDN, and GSDN are transmitted to the motor generator control unit 32.

  The motor generator control unit 32 receives the drive command GI, performs PWM processing, generates a source signal for the drive signals of the IGBT elements Q3 to Q8 in the inverter 14, and receives the drive command MI and performs PWM processing. The motor control unit 55 that performs processing and generates a signal that is the source of the drive signal of the IGBT element in the inverter 22, and receives the boost command CI and performs PWM processing to And a boost converter control unit 56 for generating an original signal.

  The motor generator control unit 32 further includes a gate blocking unit 57 that blocks the output of the generator control unit 54 with a prohibition signal GSDN, a gate blocking unit 58 that blocks the output of the motor control unit 55 with a prohibition signal MSDN, and boost converter control And a gate blocking unit 59 that blocks the output of the unit 56 with a prohibition signal CSDN.

  The hybrid control unit 31 calculates the VH overvoltage detection threshold value VHov based on the coolant temperature Tw. When the voltage VH detected by the voltage sensor 13 exceeds the VH overvoltage detection threshold value VHov, it is determined as an overvoltage, and the hybrid control unit 31 detects this and activates the inhibition signals GSDN, MSDN, CSDN, and the boost converter 12, The inverter 14 and the inverter 22 are shut down.

  When the voltage VH falls below a predetermined overvoltage, the shutdown is not immediately released even if the voltage VH falls below the predetermined overvoltage, and the activation (gate cut-off state) of the inhibition signals GSDN, MSDN, and CSDN is Maintained.

  Then, hybrid control unit 31 determines a threshold voltage for returning the operation of boost converter 12 when voltage VH decreases, based on water temperature Tw output from water temperature sensor 27 and atmospheric pressure P output from atmospheric pressure sensor 29. The threshold voltage is made to coincide with the target voltage of the voltage VH after the operation is restored. Thereby, it is possible to prevent the voltage from changing suddenly when the prohibition of the operation of the boost converter is canceled, and it is possible to prevent overcurrent of the boost converter and overcharge of the battery. Further, since the target voltage and the return threshold voltage of the voltage VH are made variable based on the temperature and the atmospheric pressure, the boost converter performance that matches the component withstand voltage can be exhibited.

  The control device 30 described above with reference to FIG. 2 can also be realized by software using a computer.

  FIG. 3 is a diagram showing a general configuration when a computer 180 is used as the control device 30.

  With reference to FIG. 3, a computer 180 includes a CPU 185, an A / D converter 181, a ROM 182, a RAM 183, and an interface unit 184.

  The A / D converter 181 converts an analog signal AIN such as an output of various sensors into a digital signal and outputs it to the CPU 185. The CPU 185 is connected to a ROM 182, a RAM 183, and an interface unit 184 via a bus 186 such as a data bus or an address bus to exchange data.

  The ROM 182 stores data such as a program executed by the CPU 185 and a map to be referred to. The RAM 183 is a work area when the CPU 185 performs data processing, for example, and temporarily stores various variables.

  The interface unit 184 communicates with other ECUs, inputs rewrite data when an electrically rewritable flash memory or the like is used as the ROM 182, or a computer such as a memory card or CD-ROM. The data signal SIG is read from a readable recording medium.

  Note that the CPU 185 transmits and receives a data input signal DIN and a data output signal DOUT from the input / output port.

  The control device 30 is not limited to such a configuration, and may be realized including a plurality of CPUs.

FIG. 4 is a flowchart showing a control structure of processing executed by the control device 30.
Referring to FIGS. 1 and 4, first, in step S <b> 1, control device 30 calculates VH overvoltage detection threshold VHov based on coolant temperature Tw. For example, a map in which the water temperature Tw is associated with the threshold value VHov is prepared in advance based on experiments. In step S1, the threshold value VHov may be obtained by referring to the map based on the output of the water temperature sensor in FIG.

FIG. 5 is a diagram showing an example of a VH overvoltage detection threshold map.
In FIG. 5, the horizontal axis represents the temperature of the cooling water that cools the inverter and the voltage converter, and the vertical axis represents the VH overvoltage detection threshold VHov. Then, as the coolant temperature shown in FIG. 5 rises, the voltage VHov increases stepwise, and hysteresis is provided at two locations when the coolant temperature is rising and when the coolant temperature is falling. It may be a stepped line. Further, the voltage VHov may change linearly or in a curved line even if it is not particularly stepped.

  Subsequent to step S1 in FIG. 4, in step S2, it is determined whether or not the voltage VH measured by the voltage sensor 13 is greater than the VH overvoltage detection threshold value VHov. If VH> VHov is not satisfied, the voltage VH is not an overvoltage, and thus the processing of this flowchart ends in step S7. On the other hand, if VH> VHov is established in step S2, the process proceeds to step S3.

  In step S3, the inverter or voltage converter is shut off in order to prevent the IPM (Intelligent Power Module) of the inverter or voltage converter from being damaged beyond its withstand voltage. The gate cutoff corresponds to, for example, fixing the gate of an IGBT element or the like to an inactivated state and prohibiting activation.

  Subsequently, in step S4, the gate permission determination threshold value VHa is calculated based on the water temperature Tw measured by the water temperature sensor 27 and the atmospheric pressure P measured by the atmospheric pressure sensor 29. In step S5, it is determined whether or not the voltage VH is lower than the gate permission determination threshold value VHa. The gate permission determination threshold value VHa is adopted as the target voltage VH * of the voltage VH when the gate cutoff is released.

  FIG. 6 is a block diagram illustrating processing for setting the gate permission determination threshold value determined in step S4 of FIG.

  Referring to FIG. 6, a map 202 defines a coolant water temperature on the horizontal axis and a voltage on the vertical axis. Then, by inputting the water temperature measured by the water temperature sensor 27, the corresponding boosted voltage upper limit value is output from the map 202. For example, the withstand voltage (withstand voltage) of an IPM of an inverter or a voltage converter has a characteristic that varies with temperature. In some IPM examples, the withstand voltage is low at low temperatures.

  On the other hand, in the map 204, atmospheric pressure is defined on the horizontal axis, and voltage is defined on the vertical axis. Then, when the atmospheric pressure measured by the atmospheric pressure sensor 29 is input, the corresponding boosted voltage upper limit value is output from the map 204. For example, the withstand voltage (withstand voltage) of the motor generator has a characteristic that varies depending on atmospheric pressure. In an example of a motor generator, the withstand voltage decreases as the atmospheric pressure decreases.

  Thus, when two candidates for the boost voltage upper limit value are output from the maps 202 and 204, in block 206, the smaller one of the two candidates for the boost voltage upper limit value is determined as the gate permission determination threshold value VHa.

  Thus, when the gate permission determination threshold value VHa is set in step S4 of FIG. 4, it is determined in step S5 whether or not the voltage VH is smaller than the gate permission determination threshold value VHa. If VH <VHa is not established, the process returns to step S3 again, and the calculation of the threshold value in step S4 and the determination of the VH voltage in step S5 are repeated while the gate is cut off in step S3.

  If the voltage VH drops and VH <VHa is established, the process proceeds from step S5 to step S6. In step S6, gate permission, that is, switching on / off of the gates of IGBT elements Q1 and Q2, which are switching elements of boost converter 12 in FIG. 1, is permitted. As a result, the boost converter 12 can perform a boost operation. At this time, target value VH * of voltage VH of boost converter 12 is initially set to VHa. By doing so, it is possible to avoid an overcurrent flowing through the boost converter 12 or an overcharge of the battery B.

When gate permission is made in step S6, the process ends in step S7.
FIG. 7 is a waveform diagram for explaining overvoltage protection and its release according to the present embodiment.

  Referring to FIG. 7, VH overvoltage detection threshold value VHov is a threshold value at which the gate of the voltage converter is cut off when voltage VH exceeds this value. The VH overvoltage detection threshold value VHov is a value that is set in step S1 of FIG. 4 and changes depending on the coolant temperature.

  The boost voltage upper limit value VHmax is a voltage at which the boost voltage target value VH * does not exceed this value regardless of changes in water temperature or atmospheric pressure.

  The gate permission determination threshold value VHa indicates how much the voltage VH drops after the overvoltage of the voltage VH is detected, and when the voltage VH drops, permits the operation of the voltage converter again. This is the threshold value shown. The gate permission determination threshold value VHa is set in step S4 of FIG. 4 so as to be lower than VHmax and change depending on the atmospheric pressure and the water temperature.

  At time t0, the boost target voltage and the gate permission voltage are set equal to VHa. However, it is assumed that the voltage VH rises between time t0 and time t1 for some reason and exceeds the VH overvoltage detection threshold value VHov at time t1.

  Then, as a result of the processing proceeding from step S2 to step S3 in FIG. 4 at time t1, the gate cutoff command CSDN is activated. As a result, IGBT elements Q1, Q2 of boost converter 12 are both fixed to the off state, and the boost operation is prohibited.

  The voltage VH becomes lower than the VH overvoltage detection threshold VHov before the time t2, but the activation of the gate cutoff command CSDN is maintained between the times t1 and t2.

  At time t2, when the voltage VH becomes smaller than the gate permission determination threshold value VHa, the gate cutoff command CSDN is canceled and the gate permission state is entered. Here, if the voltage VH immediately after gate permission is different from the target voltage VH *, an overcurrent may occur in the voltage converter or an overcharge may be induced in the battery. However, in the present embodiment, immediately after gate permission, boost target voltage VH * is set equal to gate permission determination threshold value VHa. This prevents an overcurrent from flowing in order for the voltage converter to adjust the voltage VH to the target voltage VH *.

  Finally, the present embodiment will be generally described with reference to FIG. 1 again. The motor drive device disclosed in the present embodiment boosts the voltage of the motor (motor generator MG2) for driving the wheels, inverter 22 for driving the motor, battery B as the power storage device, and the power storage device. A voltage converter (boost converter 12) for supplying the first voltage VH to the inverter 22, a voltage sensor 13 for detecting the first voltage VH supplied from the voltage converter to the inverter, and a value representing the state of the motor drive device And a control device 30 that controls the inverter 22 and the voltage converter according to the output of the voltage sensor 13. The value representing the state of the motor drive device is, for example, a value that affects the boost voltage upper limit value of the boost converter. The control device 30 prohibits the operation of the voltage converter when the first voltage VH exceeds the first threshold voltage (VHov), and then the second voltage is lower than the first threshold voltage. When the voltage drops below the threshold voltage (VHa), the prohibition of the operation on the voltage converter is canceled. At this time, the control device 30 changes the second threshold voltage (VHa) according to the output of the state detection sensor.

Preferably, the state detection sensor includes an atmospheric pressure sensor 29 that detects atmospheric pressure.
Preferably, the state detection sensor includes a water temperature sensor 27 that detects temperature.

  Preferably, control device 30 changes the target voltage of the voltage converter in accordance with the output of the state detection sensor. When the prohibition of the operation on the voltage converter is canceled, the target voltage VH * and the second threshold voltage (VHa) are set to the same value.

  As shown in FIGS. 1 and 4, according to another aspect of the present invention, a motor (motor generator MG2) for driving wheels, an inverter 22 for driving the motor, battery B as a power storage device, and power storage A voltage converter (boost converter 12) that boosts the voltage of the device and supplies the first voltage VH to the inverter, a voltage sensor 13 that detects the first voltage VH supplied from the voltage converter to the inverter 22, and a motor drive A method for controlling a motor drive device including a state detection sensor (FIG. 3: water temperature sensor 27, atmospheric pressure sensor 29) for detecting a value representing a state of the device, wherein the first voltage exceeds a first threshold voltage In this case, after the step of prohibiting the operation of the voltage converter (steps S2 and S3) and the first voltage exceeds the first threshold voltage, the first voltage is the first threshold value. A step of releasing the prohibition of the operation on the voltage converter when the voltage drops below a second threshold voltage lower than the pressure (step S5), and a step of changing the second threshold voltage according to the output of the state detection sensor (step S4). ). The value representing the state of the motor drive device is, for example, a value that affects the boost voltage upper limit value of the boost converter.

  Preferably, the control method changes the target voltage of the voltage converter according to the output of the state detection sensor and sets the target voltage and the second threshold voltage to the same value when the prohibition of the operation on the voltage converter is canceled. A step (step S6) is further provided.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is a diagram illustrating a main configuration of a vehicle 100 according to an embodiment of the present invention. It is a functional block diagram of the control apparatus 30 of FIG. 2 is a diagram illustrating a general configuration when a computer 180 is used as a control device 30. FIG. 3 is a flowchart illustrating a control structure of processing executed by a control device 30. It is the figure which showed an example of the map of a VH overvoltage detection threshold value. FIG. 5 is a block diagram illustrating processing for setting a gate permission determination threshold value determined in step S4 of FIG. 4. It is a wave form diagram for demonstrating the overvoltage protection of this Embodiment, and its cancellation | release.

Explanation of symbols

  2 wheel, 3 power split mechanism, 4 engine, 10, 13, 21 voltage sensor, 11, 24 current sensor, 12 boost converter, 14, 22 inverter, 15 U phase arm, 16 V phase arm, 17 W phase arm, 23 Load circuit, 26 accelerator position sensor, 27 water temperature sensor, 28 vehicle speed sensor, 29 barometric pressure sensor, 30 control device, 31 hybrid control unit, 32 motor generator control unit, 34,181 A / D converter, 35 register, 40 connection unit , 42 Electric air conditioner, 44 DC / DC converter, 46 Auxiliary battery, 54 Generator control unit, 55 Motor control unit, 56 Boost converter control unit, 57-59 Gate cutoff unit, 100 vehicle, 180 computer, 184 interface unit, 186 Bus, 202, 20 4 maps, 206 blocks, B battery, C1, C2 capacitor, D1-D8 diode, L1 reactor, MG1, MG2 motor generator, PL1, PL2 power line, Q1-Q8 IGBT element, R1 resistor, R2 discharge resistor, SL ground Line, SMR1-SMR3 System main relay.

Claims (6)

A motor drive device,
A motor for driving the wheels;
An inverter for driving the motor;
A power storage device;
A voltage converter that boosts a voltage of the power storage device and supplies a first voltage to the inverter;
A voltage sensor for detecting the first voltage supplied from the voltage converter to the inverter;
A state detection sensor for detecting a value affecting the component pressure resistance of the motor drive device;
A control device for controlling the inverter and the voltage converter according to the output of the voltage sensor;
The control device prohibits the operation of the voltage converter when the first voltage exceeds a first threshold voltage, and then the second voltage is lower than the first threshold voltage. Release the prohibition of the operation to the voltage converter when it falls below the threshold voltage,
Said controller, in response to an output of the state detection sensor, changing the target voltage and the second threshold voltage of said voltage converter,
The motor drive device , wherein the target voltage and the second threshold voltage are set equal to each other when the prohibition of the operation on the voltage converter is canceled .   The motor driving apparatus according to claim 1, wherein the state detection sensor includes a sensor that detects atmospheric pressure.   The motor driving apparatus according to claim 1, wherein the state detection sensor includes a sensor that detects a temperature. A method for controlling a motor drive device, the motor drive device comprising: a motor for driving a wheel; an inverter for driving the motor; a power storage device; and a voltage for the power storage device boosted to the inverter. A voltage converter that supplies a voltage of 1, a voltage sensor that detects the first voltage supplied from the voltage converter to the inverter, and a state detection sensor that detects a value that affects a component breakdown voltage of the motor drive device viewing including the door,
Prohibiting the operation of the voltage converter if the first voltage exceeds a first threshold voltage;
After the first voltage exceeds the first threshold voltage, the prohibition on the operation of the voltage converter is canceled when the first voltage falls below a second threshold voltage lower than the first threshold voltage. And steps to
Changing the second threshold voltage according to the output of the state detection sensor ;
Changing the target voltage of the voltage converter according to the output of the state detection sensor, and setting the target voltage and the second threshold voltage to be equal when releasing the prohibition of the operation of the voltage converter; A method for controlling a motor driving device. The method of controlling a motor driving device according to claim 4 , wherein the state detection sensor includes a sensor that detects atmospheric pressure. The state detecting sensor comprises a sensor for detecting the temperature, the control method of the motor driving device according to claim 4 or 5.

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