JP2012130098A - Electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine an inverter in which an off-failure does not occur, while increasing opportunities for promptly shifting to a state in which a vehicle runs by use of a motor driven by an inverter in which the off-failure, which prevents a part of a plurality of switching elements from being switched to on from off, does not occur.SOLUTION: When it is determined that battery charge/discharge current Ib does not fall within an allowable current range and a one-phase open fault occurs in either of two inverters while the vehicle runs with the two motors driven (S100, S110), the inverter is controlled so that electric running, in which the vehicle runs with only a second motor driven, is carried out, and the gate of the inverter that drives a first motor is blocked (S120). In addition, it is determined in which of the inverters the one-phase open fault occurs, on the basis of whether the charge/discharge current Ib falls within the allowable rage or not until a predetermined time period tb1 has passed from the start of the electric running (S130-S180).

Description

  The present invention relates to an electric vehicle, and more specifically, a plurality of motors driven by three-phase alternating current and capable of outputting power required for traveling, and a plurality of inverters each having a plurality of switching elements and driving a plurality of motors. The present invention relates to an electric vehicle including a secondary battery capable of exchanging electric power with a plurality of motors via a plurality of inverters.

  Conventionally, this type of electric vehicle includes a first motor (MG1) that is driven when an engine that outputs power for traveling is driven, a second motor (MG2) that outputs power for traveling, There has been proposed a hybrid vehicle including two inverters that respectively drive two motors and a DC power source that can exchange power with the two motors via the two inverters (see, for example, Patent Document 1). In this vehicle, when two motors are driven, the detected value of the direct current of the direct current power source by the current sensor is compared with the estimated value of the direct current calculated based on the power balance in the entire motor drive system, When the deviation between the two is greater than or equal to the threshold value, the fluctuation frequency of the DC current is calculated, and it is detected that a one-phase open failure has occurred in the inverter that drives the motor having a rotational speed synchronized with the calculated fluctuation current of the DC current. To do. Then, the inverter that is detected as having a one-phase open failure is gated, and an abnormal operation (retreat operation) is performed using a motor corresponding to the other inverter.

JP 2010-178556 A

  However, in the above-described electric vehicle, two motors are driven to run until an inverter in which a one-phase open failure has occurred is identified. A certain amount of time is required until the inverter is gate cut off and the state moves to the state of retreating using only the motor driven by the other inverter. In this case, if the motor is driven by the inverter in which the one-phase open failure has occurred and the running time becomes long, the DC current of the DC power supply fluctuates beyond the allowable range, and the DC power supply is charged / discharged by an excessive current. Inconvenience such as failure may occur.

  While the electric vehicle of the present invention increases the opportunity to quickly shift to a state of running using a motor driven by an inverter that does not cause an off abnormality that makes it impossible to turn on some of the plurality of switching elements, The main purpose is to discriminate an inverter in which an off abnormality has not occurred.

  The electric vehicle of the present invention employs the following means in order to achieve the main object described above.

The electric vehicle of the present invention is
A plurality of motors driven by three-phase alternating current and capable of outputting power required for traveling, a plurality of inverters each having a plurality of switching elements and driving the plurality of motors, and the plurality of inverters via the plurality of inverters An electric vehicle comprising a secondary battery capable of exchanging electric power with the motor of
Battery current detecting means for detecting a battery current which is a current for charging and discharging the secondary battery;
Phase current detection means for detecting a phase current flowing in each phase of the plurality of motors;
An off state in which a part of the plurality of switching elements cannot be turned on from any of the plurality of inverters based on the detected battery current while the plurality of motors are driven to travel. When it is determined that an abnormality has occurred, an inverter that drives the predetermined motor among the plurality of inverters is controlled so that only a predetermined motor that is a part of the plurality of motors is driven to travel. In addition, the gate of an inverter different from the inverter that drives the predetermined motor is cut off, and only the predetermined motor is driven and running while the detected battery current or the detected phase current is Determination control means for determining whether or not the off abnormality has occurred in an inverter that drives a predetermined motor;
It is a summary to provide.

  In the electric vehicle according to the present invention, a plurality of switching is performed by any one of the plurality of inverters based on a battery current that is a current for charging and discharging the secondary battery while the plurality of motors are driven to travel. When it is determined that an off abnormality has occurred in which part of the element cannot be turned on from off, only a predetermined motor, which is a part of the plurality of motors, is driven to run. Among them, the inverter that drives the predetermined motor is controlled and the gate of the inverter different from the inverter that drives the predetermined motor is shut off. That is, when it is determined that an off abnormality has occurred in this way, it is not possible to determine which of the plurality of inverters has an off abnormality, but first, only a predetermined motor is driven to run. The inverter which drives a predetermined motor among several inverters is controlled, and the gate of the inverter different from the inverter which drives a predetermined motor is interrupted | blocked. As a result, when an off abnormality has occurred in the inverter that has shut off the gate, the motor can be driven using a motor (in this case, a predetermined motor) driven by the inverter in which the off abnormality has not occurred. . Whether or not an off abnormality has occurred in the inverter driving the predetermined motor based on the battery current or the phase current flowing in each phase of the plurality of motors while only the predetermined motor is driven. judge. As a result, among the plurality of inverters, whether an off abnormality has occurred in an inverter that drives a predetermined motor, or whether an off abnormality has occurred in an inverter that is different from the inverter that drives the predetermined motor, that is, an inverter that has shut off the gate. Can be determined. As a result, it is possible to determine the inverter in which the off abnormality has not occurred while increasing the opportunity to quickly shift to the state of traveling using the motor driven by the inverter in which the off abnormality has not occurred.

  In such an electric vehicle according to the present invention, the determination control means detects the battery current detected until a predetermined time elapses after the control is started so that only the predetermined motor is driven to travel. Is outside the allowable current range set as the allowable range when charging and discharging the secondary battery, it is determined that the off abnormality has occurred in the inverter that drives the predetermined motor, and the detected When the battery current does not fall outside the allowable current range, it is means for determining that the off abnormality has occurred in an inverter different from the inverter driving the predetermined motor among the plurality of inverters. it can. In this way, an off abnormality has occurred in the inverter that drives the predetermined motor among the plurality of inverters, or an off abnormality has occurred in the inverter that is different from the inverter that drives the predetermined motor, that is, the inverter that has shut off the gate. Can be determined more reliably.

  Further, in the electric vehicle according to the present invention, the plurality of inverters include a proportional term and an integral term so that the detected phase current has a value corresponding to a torque command to be output from the motor for each of the motors driven. The determination control means performs control so that the inverter that drives the predetermined motor is controlled by the command value and only the predetermined motor is driven to run. The absolute value of the command value in the feedback control is outside the allowable value range set as the allowable range when charging and discharging the secondary battery until a predetermined time elapses from the start. It is determined that the off abnormality has occurred in the inverter that drives the predetermined motor, and the absolute value of the command value is the allowable value. The inverter for driving the predetermined motor among the plurality of inverters when not become 囲外 is the determining means is the off-failure occurs in different inverter may be a thing. In this way, an off abnormality has occurred in the inverter that drives the predetermined motor among the plurality of inverters, or an off abnormality has occurred in the inverter that is different from the inverter that drives the predetermined motor, that is, the inverter that has shut off the gate. Can be determined more reliably. In this case, the predetermined motor is a motor whose rotational speed increases as the vehicle speed increases, and the determination control means is configured such that the vehicle speed is set to an upper limit that is set in advance while only the predetermined motor is driven. It may be a means for controlling the plurality of inverters so that only the predetermined motor is driven and travels within a range of vehicle speed or less. In this way, the magnitude of the back electromotive force generated in the predetermined motor can be suppressed, and the absolute value of the feedback control command value of the inverter that drives the predetermined motor is out of the allowable range due to the back electromotive force generated in the predetermined motor. Can be suppressed. As a result, it is possible to suppress erroneous determination that an off abnormality has occurred in the inverter that drives the predetermined motor.

  Further, in the electric vehicle according to the present invention, the determination control means is allowed when the detected battery current charges and discharges the secondary battery while the plurality of motors are driven to travel. It may be a means for determining that the off-abnormality has occurred in any of the plurality of inverters when it falls outside the second allowable current range set as the range. By so doing, it can be more reliably determined that an off abnormality has occurred in any of the plurality of inverters.

  Alternatively, in the electric vehicle according to the present invention, the determination control unit determines that the off abnormality has occurred in the inverter that drives the predetermined motor while only the predetermined motor is being driven. Sometimes, the plurality of inverters are controlled so that only a motor different from the predetermined motor among the plurality of motors is driven to travel, and the inverter different from the inverter driving the predetermined motor among the plurality of inverters is When it is determined that an off abnormality has occurred, only the predetermined motor is driven, and the plurality of inverters may be controlled so as to continue running. In this way, it is possible to increase the opportunity to shift to a state where the vehicle travels using a motor driven by an inverter in which no off abnormality has occurred.

  Further, in the electric vehicle of the present invention, there are three internal shafts including an internal combustion engine, an output shaft of the internal combustion engine, a rotation shaft of a first motor that is one of the plurality of motors, and a drive shaft connected to the axle. A planetary gear mechanism to which a rotating element is connected, and a second motor that is the remaining one of the plurality of motors may be connected to the drive shaft.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as a first embodiment of the present invention. It is a block diagram which shows the outline of a structure of the electric drive system containing motor MG1, MG2. It is a flowchart which shows an example of the failure determination routine performed by the hybrid electronic control unit 70 of 1st Example. It is a flowchart which shows an example of the electric travel drive control routine performed by the electronic control unit for hybrid 70 of 1st Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship of the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 at the time of evacuation travel by electric travel. 4 is a flowchart showing an example of a straight traveling drive control routine executed by a hybrid electronic control unit 70. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship of the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 at the time of carrying out evacuation driving | running | working by a straight drive. It is a flowchart which shows an example of the failure determination routine performed by the hybrid electronic control unit 70 of 2nd Example. It is a flowchart which shows an example of the electric travel drive control routine performed by the hybrid electronic control unit 70 of 2nd Example. It is explanatory drawing which shows an example of the map for a load factor setting. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 320 of a modified example.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a block diagram showing an outline of the configuration of a hybrid vehicle 20 as a first embodiment of the present invention, and FIG. 2 is a block diagram showing an outline of the configuration of an electric drive system including motors MG1 and MG2. . As shown in FIG. 1, the hybrid vehicle 20 according to the embodiment includes an engine 22, a three-shaft power distribution and integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, A motor MG1 capable of generating electricity connected to the distribution integration mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution integration mechanism 30, and a motor MG2 connected to the reduction gear 35 A chargeable / dischargeable battery 50, a boost converter 55 that boosts the electric power from the battery 50 and supplies the boosted electric power to the motors MG1, MG2, and a hybrid electronic control unit 70 that controls the entire vehicle.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is under operation control such as fuel injection control, ignition control, intake air amount control. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62. Therefore, the motor MG1 is a motor that can output the power necessary for outputting the driving power from the engine 22 to the ring gear shaft 32a as the drive shaft, and the motor MG2 is the ring gear shaft using the driving power as the drive shaft. Since the motor can output to 32a, the motors MG1 and MG2 can be said to be motors that can output the power required for traveling.

  As shown in FIG. 2, each of the motor MG1 and the motor MG2 is configured as a well-known synchronous generator motor including a rotor having a permanent magnet attached to an outer surface and a stator wound with a three-phase coil. . The inverters 41 and 42 include transistors T11 to T16 and T21 to 26 as six switching elements, and six diodes D11 to D16 and D21 to D26 connected in parallel to the transistors T11 to T16 and T21 to T26 in the reverse direction. It is configured. The transistors T11 to T16 and T21 to T26 are arranged in pairs so that each of the inverters 41 and 42 is on the source side and the sink side with respect to the positive and negative buses shared as the power line 54. Each of the three-phase coils (U-phase, V-phase, W-phase) of the motors MG1, MG2 is connected to each connection point between the transistors. Therefore, by controlling the on-time ratio of the transistors T11 to T16 and T21 to T26 that make a pair while the voltage is acting between the positive electrode bus and the negative electrode bus of the power line 54, a rotating magnetic field is applied to the three-phase coil. And the motors MG1 and MG2 can be driven to rotate. Moreover, since the inverters 41 and 42 share the electric power line 54, electric power generated by either the motor MG1 or MG2 can be supplied to another motor. A smoothing capacitor 57 is connected to the positive and negative buses of the power line 54.

  As shown in FIG. 2, boost converter 55 is connected to power line 56 connected to battery 50 and power line 54 shared by inverters 41 and 42, and includes transistors T31 and T32 serving as two switching elements. It comprises two diodes D31 and D32 and a reactor L connected in parallel to the transistors T31 and T32. The two transistors T31 and T32 are respectively connected to the positive and negative buses of the power line 54, and the reactor L is connected to the connection point of the transistors T31 and T32 and the positive bus of the power line 56. Further, the positive electrode terminal and the negative electrode terminal of the battery 50 are connected to the positive electrode bus and the negative electrode bus, respectively. Therefore, by turning on and off the transistors T31 and T32, the voltage of the DC power of the battery 50 is boosted and supplied to the inverters 41 and 42, or the DC voltage acting on the power line 54 is stepped down to charge the battery 50. You can do it. Also, a smoothing capacitor 58 is connected to the positive and negative buses of the power line 56. Hereinafter, the power line 54 side from the boost converter 55 is referred to as a high voltage system, and the battery 50 side from the boost converter 55 is referred to as a low voltage system.

  The motors MG1, MG2 and the boost converter 55 are all driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, such as rotational positions θm1 and θm2 from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and the motor MG1. , The phase currents Iv1, Iw1, Iv2, Iw2 from the current sensors 45V, 45W, 46V, 46W for detecting the phase currents flowing in the V-phase and W-phase of the three-phase coil of MG2, and the capacitor 57 attached to the power line 54 The voltage VH of the high voltage system from the voltage sensor 57 that detects the voltage between the terminals, the voltage VL of the low voltage system from the voltage sensor 58 that detects the voltage between the terminals of the capacitor 58 attached to the power line 56, the voltage of the boost converter 55 Reactor current IL from current sensor 59 connected to the connection point of transistors T31 and T32 and reactor L From the motor ECU 40, switching signals to the transistors T11 to T16 and T21 to T26 as switching elements of the inverters 41 and 42 and switching signals to the transistors T31 and T32 as switching elements of the boost converter 55 are input. Etc. are output. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the electrical angles θe1 and θe2 of the motors MG1 and MG2 and the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions θm1 and θm2 from the rotational position detection sensors 43 and 44.

  The battery 50 is configured as a lithium ion secondary battery, for example, and is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 includes signals necessary for managing the battery 50, for example, the voltage Vb between the terminals from the voltage sensor 51 a installed between the terminals of the battery 50, and the power line 56 connected to the positive terminal of the battery 50. The charging / discharging current Ib from the current sensor 51b attached to the positive bus, the battery temperature Tb from the temperature sensor 51c attached to the battery 50, and the like are input, and data on the state of the battery 50 is communicated as necessary. Output to the hybrid electronic control unit 70. Further, the battery ECU 52 is a ratio of the amount of stored electricity stored in the battery 50 based on the integrated value of the charge / discharge current Ib detected by the current sensor 51b in order to manage the battery 50 to the total capacity (storage capacity). The storage ratio SOC is calculated, and the input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the calculated storage ratio SOC and the battery temperature Tb. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input limiting limit are set based on the storage ratio SOC of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. The required torque is controlled by operating the engine 22 so that the engine 22 is operated at a predetermined number of revolutions while the drive of the motor MG2 is stopped, and receiving the torque from the motor MG1 by the engine 22 via the power distribution integration mechanism 30. There is a direct operation mode in which the motor MG1 is driven and controlled so that is output to the ring gear shaft 32a. Here, both the torque conversion operation mode and the charge / discharge operation mode are modes for controlling the engine 22 and the motors MG1, MG2 so that the required power is output to the drive shaft 32 with the operation of the engine 22. Both are referred to as the engine operation mode. In addition, the drive control of the motors MG1 and MG2 in the engine operation mode, the drive control of the motor MG2 in the motor operation mode, and the drive control of the motor MG1 in the direct operation mode are performed by charging and discharging due to an excessive current of the battery 50. It is performed within the range of the input / output limit Win, Wout of the battery 50 so that there is no.

  In the embodiment, the inverters 41 and 42 for driving the motors MG1 and MG2 are controlled by a pulse width modulation (PWM) control method. In the PWM control method, an output voltage having a sine wave fundamental wave component is obtained by switching control based on a pulse width modulation (PWM) signal generated using a sine wave voltage command signal and a carrier signal (triangular wave signal) which is a carrier wave. It is a method to obtain. For example, the inverter 42 for driving the motor MG2 is controlled from the rotational position detection sensor 44 by setting the sum of the phase currents Iu2, Iv2, Iw2 flowing in the U phase, V phase, and W phase of the three-phase coil of the motor MG2 to 0. Using the electrical angle θe2 of the motor 22 obtained from the rotational position θm2, the phase currents Iv2 and Iw2 from the current sensors 46V and 46W are coordinate-converted into d-axis and q-axis currents Id and Iq (three-phase to two-phase conversion). The d-axis is based on the torque command Tm2 * using a map in which the relationship between the torque command Tm2 * to be output from the motor MG2 and the target currents Id * and Iq * of the d-axis and q-axis is determined in advance through experiments or the like. , Q-axis target currents Id * and Iq * are set, feedback control using the d-axis and q-axis currents Id and Iq is performed on the set target currents Id * and Iq *, and the following equation (1) and The d-axis and q-axis voltage commands Vd * and Vq * are set by the equation (2), and the d-axis and q-axis voltage commands Vd * and Vq * are set to U of the three-phase coil of the motor MG2 using the electrical angle θe2. Coordinate conversion (two-phase to three-phase conversion) into voltage commands Vu *, Vv *, and Vw * to be applied to the phase, V phase, and W phase, and converting the voltage commands Vu *, Vv *, and Vw * into the inverter 42 This is performed by switching the inverter 42 using the PWM signal as a switching signal. In equations (1) and (2), “Kp1” and “Kp2” in the first term on the right side corresponding to the proportional term are proportional coefficients, and “Ki1” and “Ki2” in the second term on the right side corresponding to the integral term. "Is an integral coefficient.

Vd * = Kp1 (Id * -Id) + Ki1Σ (Id * -Id) (1)
Vq * = Kp2 (Iq * -Iq) + Ki2Σ (Iq * -Iq) (2)

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, in particular, an abnormality in which one of the six switching elements cannot be turned on from one of the inverters 41 and 42 for driving the motors MG1 and MG2 (hereinafter referred to as one phase). The operation when an open failure occurs) will be described. FIG. 3 is a flowchart showing an example of a failure determination routine executed by the hybrid electronic control unit 70. This routine is executed when traveling in the engine operation mode is started, that is, when traveling is started with both of the motors MG1 and MG2 being driven.

  When the failure determination routine is executed, the CPU 72 of the hybrid electronic control unit 70 first inputs the charge / discharge current Ib from the current sensor 51b connected to the positive terminal of the battery 50 from the battery ECU 52 by communication (step S100). ), A process of determining whether or not the input charging / discharging current Ib is within an allowable current range allowed when charging / discharging the battery 50 is executed (step S110). Here, in the embodiment, the allowable current range is not less than the minimum allowable current Ibmin obtained by dividing the input limit Win of the battery 50 by the terminal voltage Vb from the voltage sensor 51a, and the output limit Wout of the battery 50 is the voltage sensor. The maximum allowable current Ibmax obtained by dividing by the inter-terminal voltage Vb from 51a was assumed to be in the range.

  When the charge / discharge current Ib of the battery 50 is within the allowable current range, that is, when the charge / discharge current Ib is not less than the minimum allowable current Ibmin and not more than the maximum allowable current Ibmax, the process returns to step S100. When the charge / discharge current Ib of the battery 50 is outside the allowable current range, is the one-phase open failure occurring in the inverter 41 that drives the motor MG1 or the inverter 42 that drives the motor MG2? However, it is determined that a one-phase open failure has occurred in one of the inverters 41 and 42, and an operation stop command for the engine 22 is transmitted to the engine ECU 24 (step S115), and the inverter 41 that drives the motor MG1 is turned on. As one of the operation modes in which the vehicle is retracted while the gate is cut off, the motor operation mode is started (hereinafter, the driving in this state is referred to as electric driving) (step S120). The engine ECU 24 that has received the operation stop command for the engine 22 stops operation control such as fuel injection control and ignition control of the engine 22. When the charge / discharge current Ib of the battery 50 falls outside the allowable current range, it is determined that a one-phase open failure has occurred in one of the inverters 41 and 42 because the phase current of the phase in which the one-phase open failure has occurred is half In order to form a wave rectification waveform, the voltage VH of the high voltage system varies, and the charge / discharge current Ib of the battery 50 varies. Here, the description of the failure determination will be temporarily interrupted, and the drive control for performing the electric travel will be described. FIG. 4 is a flowchart showing an example of an electric travel drive control routine executed by the hybrid electronic control unit 70 when performing electric travel.

  When the electric travel drive control routine is executed, first, the CPU 72 of the hybrid electronic control unit 70 first determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm2, of the motor MG2. A process of inputting data necessary for control such as input / output restrictions Win and Wout of the battery 50 is executed (step S200). Here, the rotation speed Nm2 of the motor MG2 is calculated based on the rotation position θm2 of the rotor of the motor MG2 detected by the rotation position detection sensor 44, and is input from the motor ECU 40 by communication. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 and the storage ratio SOC of the battery 50 and are input from the battery ECU 52 by communication.

  When the data is thus input, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. Is set (step S210). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 5 shows an example of the required torque setting map.

  Subsequently, by dividing the required torque Tr * by the gear ratio Gr of the reduction gear 35, a temporary torque Tm2tmp, which is a temporary value of the torque to be output from the motor MG2, is calculated (step S230), and the input / output limit of the battery 50 is limited. By dividing Win and Wout by the rotational speed Nm2 of the motor MG2, torque limits Tm2min and Tm2max as upper and lower limits of the torque that may be output from the motor MG2 are calculated (step S240), and the calculated temporary torque Tm2tmp is expressed by the following formula ( The torque command Tm2 * of the motor MG2 is set by limiting with the torque limits Tm2min and Tm2max according to 3) (step S250).

  Tm2 * = max (min (Tm2tmp, Tm2max), Tm2min) (3)

  Then, the gate cutoff command of the inverter 41 that drives the motor MG1 and the set torque command Tm2 * of the motor MG2 are transmitted to the motor ECU 40 (step S260), and the electric travel drive control routine ends. The motor ECU 40 that has received the gate cutoff command of the inverter 41 and the torque command Tm2 * of the motor MG2 performs switching control of the switching element of the inverter 42 so that the motor MG2 is driven by the torque command Tm2 * with the inverter 41 gated off. To do. With this control, the motor MG2 outputs the required torque Tr * to the ring gear shaft 32a as the drive shaft while controlling the battery 50 to be charged / discharged within the range of the input / output limits Win and Wout of the battery 50. can do. FIG. 6 shows an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotating element of the power distribution and integration mechanism 30 when the vehicle is retracted by electric traveling. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. The drive control for performing electric traveling has been described above. Returning to the description of the failure determination in FIG.

  When the inverter 41 that drives the motor MG1 is gated and electric running is started, the charging / discharging current Ib from the current sensor 51b is input (step S130), and the input charging / discharging current Ib of the battery 50 is the above-mentioned. It is determined whether or not the current is within the allowable current range (step S140), and when the charge / discharge current Ib of the battery 50 is within the allowable current range, electric travel (drive control for performing electric travel) is started for a predetermined time tb1. Is determined (step S150), and when the predetermined time tb1 has not elapsed since the start of electric travel, the process returns to step S130. Here, the predetermined time tb1 is a time necessary for confirming a state in which the charge / discharge current Ib of the battery 50 does not fluctuate beyond the allowable current range, and a time determined in advance through experiments or the like can be used. . Further, the allowable current range may be different from the allowable current range used in the determination process of step S110 depending on the input / output limits Win and Wout of the battery 50. When the predetermined time tb1 elapses while the charge / discharge current Ib of the battery 50 is within the allowable current range after starting the electric travel, the fluctuation of the charge / discharge current Ib is settled by the start of the electric travel, so that the motor MG1 is driven. It is determined that a one-phase open failure has occurred in the inverter 41 that performs the operation (step S160), and the failure determination routine ends. When the failure determination routine is thus completed, the above-described drive control for performing the electric travel so as to continue the electric travel in a state where the inverter 41 is gate-cut off is continuously performed.

  When the charge / discharge current Ib of the battery 50 is outside the allowable current range after the elapse of the predetermined time tb1 since the start of the electric travel, the fluctuation of the charge / discharge current Ib does not stop even if the electric travel is started. It is determined that a one-phase open failure has occurred in the inverter 42 that drives the motor MG2 (step S170), the engine 22 is started (step S175), and the inverter 42 that drives the motor MG2 is gated off. As one of the operation modes in which the vehicle is evacuated in the state, traveling in the direct operation mode (hereinafter referred to as direct traveling) is started (step S180), and the failure determination routine is terminated. When starting the engine 22, a torque command Tm1 * of the motor MG1 is set and transmitted to the motor ECU 40 so that a predetermined motoring torque is output from the motor MG1, and the rotational speed Ne of the engine 22 is set to a predetermined ignition start rotational speed. Can be performed by transmitting a control signal to the engine ECU 24 so that fuel injection and ignition of the engine 22 are started. Next, drive control for performing the straight traveling will be described. FIG. 7 is a flowchart illustrating an example of a straight travel drive control routine that is executed by the hybrid electronic control unit 70 when performing a straight travel.

  When the straight traveling drive control routine is executed, the CPU 72 of the hybrid electronic control unit 70 executes the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm1 of the motor MG1, and the battery 50. Data necessary for control, such as input / output limits Win and Wout, is input (step S300) and connected to the drive wheels 63a and 63b as torque required for the vehicle based on the input accelerator opening Acc and vehicle speed V. The required torque Tr * to be output to the ring gear shaft 32a as the drive shaft is set using the required torque setting map illustrated in FIG. 5 (step S310), and idle rotation is performed to the target rotational speed Ne * at which the engine 22 is to be operated. The engine is set by setting a predetermined rotation speed Neset as a rotation speed larger than the number. And it transmits to ECU 24 (step S320). The engine ECU 24 that has received the target rotational speed Ne * performs intake air intake amount control, fuel injection control, ignition for adjusting the throttle opening of the engine 22 by feedback control so that the rotational speed Ne of the engine 22 becomes the target rotational speed Ne *. Performs operation control such as control.

  Subsequently, a provisional torque Tm1tmp, which is a provisional value of torque to be output from the motor MG1, is calculated by multiplying the set required torque Tr * by the product of the gear ratio ρ of the power distribution and integration mechanism 30 and the value −1 ( In step S330, torque limits Tm1min and Tm1max as upper and lower limits of torque that may be output from the motor MG1 are calculated based on the input / output limits Win and Wout of the battery 50 and the rotation speed Nm1 of the motor MG1 (step S340). Then, the calculated temporary torque Tm1tmp is limited by torque limits Tm1min and Tm1max according to the following equation (4), and a torque command Tm1 * of the motor MG1 is set (step S350). The torque limits Tm1min and Tm1max are calculated by dividing the input limit Win and output limit Wout of the battery 50 by the number of revolutions Nm1 of the motor MG1 and the torque limit Tm1min when the number of revolutions Nm1 of the motor MG1 is a positive value. The torque limit Tm1max is obtained by dividing the output limit Wout and the input limit Win of the battery 50 by the rotation speed Nm1 of the motor MG1 when the rotation speed Nm1 of the motor MG1 is a negative value. And a torque limit Tm1max.

  Tm1 * = max (min (Tm1tmp, Tm1max), Tm1min) (4)

  Then, the gate cutoff command of the inverter 42 that drives the motor MG2 and the set torque command Tm1 * of the motor MG1 are transmitted to the motor ECU 40 (step S360), and the straight travel drive control routine is terminated. The motor ECU 40 that has received the gate cutoff command of the inverter 42 and the torque command Tm1 * of the motor MG1 performs switching control of the switching element of the inverter 41 so that the motor MG1 is driven by the torque command Tm1 * with the inverter 42 being gated off. To do. With such control, the torque from the motor MG1 is received by the engine 22 while controlling the battery 50 to be charged / discharged within the range of the input / output limits Win and Wout of the battery 50, whereby the ring gear shaft 32a as the drive shaft is received. The vehicle can travel by outputting the required torque Tr *. FIG. 8 shows an example of a collinear diagram showing the dynamic relationship between the rotational speed and torque in the rotating elements of the power distribution and integration mechanism 30 when the vehicle is retracted by traveling straight. In the drawing, the thick arrow on the R axis indicates the torque that the torque Tm1 output from the motor MG1 acts on the ring gear shaft 32a. It should be noted that the above equation (1) for calculating the temporary torque Tm1tmp of the motor MG1 can be easily derived by using this alignment chart.

  According to the hybrid vehicle 20 of the first embodiment described above, the charging / discharging current Ib of the battery 50 falls outside the allowable current range while the two motors MG1 and MG2 are driven and travels. When it is determined that a one-phase open failure has occurred in one of the inverters 41 and 42, the inverter 42 is controlled and the motor MG1 is driven so that only the motor MG2 is driven and electric traveling is performed. Therefore, when the one-phase open failure occurs in the inverter 41 that has performed the gate cutoff, the motor MG2 driven by the inverter 42 in which the one-phase open failure has not occurred is used. In a retreating state. Then, during the time when the electric travel is performed in which only the motor MG2 is driven, the charging / discharging current Ib of the battery 50 is outside the allowable current range until the predetermined time tb1 elapses after the electric travel is started. It is determined that a one-phase open failure has occurred in the inverter 42 that drives the motor MG2, and the charging / discharging current Ib of the battery 50 is an allowable current until a predetermined time tb1 has elapsed since the start of electric travel. When it is within the range, it is determined that a one-phase open failure has occurred in the inverter 41 that drives the motor MG1. As a result, it is possible to determine an inverter in which a one-phase open failure has not occurred while increasing an opportunity to quickly shift to a state of traveling using a motor driven by an inverter in which a one-phase open failure has not occurred. . As a result, it is possible to increase the opportunity to suppress early charging / discharging of the battery 50 due to an excessive current due to the one-phase open failure of the inverter. Further, when it is determined that a one-phase open failure has occurred in the inverter 42 that drives the motor MG2 during the electric running in which only the motor MG2 is driven, the engine 22 is operated. Along with this, the inverter 41 is controlled so that the motor MG1 is driven to travel straight, and when it is determined that a one-phase open failure has occurred in the inverter 41 that drives the motor MG1, the electric travel is continued. Since the inverter 42 is controlled as described above, it is possible to increase the chances of shifting to a state of traveling using a motor driven by an inverter in which no one-phase open failure has occurred.

  In the hybrid vehicle 20 according to the first embodiment, during the electric traveling in which the motor MG2 is driven to travel, the charging / discharging current Ib of the battery 50 and the allowable current range are compared with each other in the inverters 41 and 42. In this case, it is specified which one-phase open failure has occurred. For this specification, it is possible to determine that a one-phase open failure has occurred in the inverter 42 during the electric running. Alternatively, it may be performed by comparing a threshold value determined in advance by an experiment or the like with the absolute value of the charge / discharge current Ib of the battery 50.

  Next, a hybrid vehicle 20B as a second embodiment of the present invention will be described. The hybrid vehicle 20B of the second embodiment has the same hardware configuration as the hybrid vehicle 20 of the first embodiment described with reference to FIG. Therefore, in order to avoid redundant description, detailed description of the hardware configuration of the hybrid vehicle 20B of the second embodiment is omitted.

  In the hybrid vehicle 20B of the second embodiment, the hybrid electronic control unit 70 replaces the failure determination routine of FIG. 3 and the electric travel drive control routine of FIG. 4 with the failure determination routine illustrated in FIG. The illustrated electric travel drive control routine is executed. The failure determination routine of FIG. 9 is the same as the failure determination routine of FIG. 3 except that the processing of steps S400 to S430 is executed instead of the processing of steps S120 to S150 of the failure determination routine of FIG. The electric travel drive control routine of FIG. 10 is the same as the electric travel drive control routine of FIG. 4 except that the processes of steps S500 to S520 are executed instead of the process of step S250 of the electric travel drive control routine of FIG. Are the same. Accordingly, the same processing among these routines is given the same step number, and detailed description thereof is omitted.

  When the failure determination routine is executed, the CPU 72 of the hybrid electronic control unit 70 inputs the charging / discharging current Ib of the battery 50, and when the input charging / discharging current Ib is outside the allowable current range, It is determined that a one-phase open failure has occurred and the operation of the engine 22 is stopped (steps S100 to S115), and only the motor MG2 is driven while the inverter 41 that drives the motor MG1 is shut off. The electric running is started in a range where the vehicle speed V is equal to or lower than the upper limit vehicle speed Vlim (step S400). Here, the description of the failure determination is temporarily interrupted, and drive control for performing electric travel will be described with reference to a flowchart showing an example of the electric travel drive control routine of FIG. The upper limit vehicle speed Vlim will be described later.

  When the electric travel drive control routine is executed, the CPU 72 of the hybrid electronic control unit 70 inputs data necessary for control and sets a required torque Tr * to be output to the ring gear shaft 32a as a drive shaft. The temporary torque Tm2tmp and torque limits Tm2min and Tm2max of MG2 are calculated (steps S200 to S240), the rated torque Tm2rat of the motor MG2 is set based on the input rotational speed Nm2, and the input vehicle speed V is determined. A load factor Rt of the motor MG2 is set (step S500), and a value obtained by multiplying the set rated torque Tm2rat by the load factor Rt is set as the upper limit torque Tm2lim of the motor MG2 (step S510). Here, the rated torque Tm2rat of the motor MG2 can be set using a map in which the relationship between the rotational speed Nm2 of the motor MG2 and the rated torque Tm2rat is predetermined based on the characteristics of the motor MG2 and stored in the RAM 74. The load factor Rt of the motor MG2 is for limiting the vehicle speed V to a range equal to or lower than the upper limit vehicle speed Vlim. A map in which the relationship between the vehicle speed V and the load factor Rt is determined in advance through experiments or the like and stored in the RAM 74 is used. Can be set using. FIG. 11 shows an example of the load factor setting map. As shown in the figure, the load factor Rt of the embodiment is a value when the vehicle speed V is equal to or lower than a value (Vlim−α) obtained by subtracting a predetermined margin α (for example, several kilometers per hour or ten kilometers per hour) from the upper limit vehicle speed Vlim. 1 is set, a value smaller than the value 1 is set as the vehicle speed V is greater than the value (Vlim−α), and a value 0 is set when the vehicle speed V is the upper limit vehicle speed Vlim.

  When the upper limit torque Tm2lim based on the upper limit vehicle speed Vlim of the motor MG2 is set in this way, the calculated temporary torque Tm2tmp is limited by the upper limit torque Tm2lim and the torque limits Tm2min and Tm2max according to the following equation (5) to set the torque command Tm2 * of the motor MG2. (Step S520), the gate cutoff command of the inverter 41 that drives the motor MG1 and the set torque command Tm2 * of the motor MG2 are transmitted to the motor ECU 40 (Step S260), and the electric travel drive control routine ends. With this control, the motor MG2 outputs the required torque Tr * to the ring gear shaft 32a as the drive shaft while controlling the battery 50 to be charged / discharged within the range of the input / output limits Win and Wout of the battery 50. can do. The drive control for performing electric traveling has been described above. Returning to the description of the failure determination in FIG.

  Tm2 * = max (min (Tm2tmp, Tm2max, Tm2lim), Tm2min) (5)

  When the inverter 41 that drives the motor MG1 is gated and the electric running is started, the q-axis voltage command Vq * in the PWM control of the inverter 42 that drives the motor MG2 is input from the motor ECU 40 by communication (step) S410), it is determined whether or not the absolute value of the input voltage command Vq * is equal to or less than the threshold value Vqref (step S420). When the absolute value of the voltage command Vq * is equal to or less than the threshold value Vqref, the electric travel (electric travel is performed). It is determined whether or not the predetermined time tb2 has elapsed since the start of the drive control) (step S430), and when the predetermined time tb2 has not elapsed since the start of electric travel, the process returns to step S410. . When a one-phase open failure occurs in the inverter 42, the q-axis current Iq obtained by coordinate conversion of the three-phase phase current including the phase current of the phase in which the failure has occurred deviates from the target current Iq *. The absolute value of the value corresponding to the integral term of the above-described equation (2) for setting the voltage command Vq * by control increases with time. Therefore, the process of determining whether or not the predetermined time tb2 has elapsed in a state where the absolute value of the voltage command Vq * is equal to or less than the threshold value Vqref is to determine whether or not a one-phase open failure has occurred in the inverter 42. It becomes processing. For this reason, as the predetermined time tb2, a time determined in advance by experiments or the like can be used as a time required to confirm a state where the absolute value of the voltage command Vq * does not exceed the threshold value Vqref (does not become excessive).

  Here, the upper limit vehicle speed Vlim used in the drive control for performing electric traveling will be described. The motor MG2 driven during the electric travel generates a larger counter electromotive force as the rotation speed Nm2 is higher. However, since this counter electromotive force causes a change in the phase voltage of the motor MG2, the rotation speed Nm2 of the motor MG2 is reduced. If it becomes higher, it may be impossible to correctly determine whether or not a one-phase open failure has occurred in the inverter 42 by comparing the absolute value of the voltage command Vq * of the inverter 42 and the threshold value Vqref. In order to avoid such a case, in the embodiment, the upper limit vehicle speed Vlim is provided in the electric traveling to suppress the increase in the rotational speed Nm2 of the motor MG2, that is, the increase in the back electromotive force of the motor MG2. Therefore, as the upper limit vehicle speed Vlim, an upper limit value of the vehicle speed range in which the determination of the occurrence of the one-phase open failure of the inverter 42 can be appropriately performed is obtained in advance through experiments or the like.

  Then, when the predetermined time tb2 elapses in a state where the absolute value of the voltage command Vq * of the inverter 42 is equal to or less than the threshold value Vqref after starting the electric travel, the absolute value of the voltage command Vq * is also increased by the start of the electric travel. Since it is not excessive, it is determined that a one-phase open failure has occurred in the inverter 41 that drives the motor MG1 (step S160), and the failure determination routine is terminated. When the failure determination routine is completed in this way, the above-described drive control (see FIG. 10) for performing the electric traveling is continued so that the electric traveling with the inverter 41 gate shut off is continued.

  On the other hand, if the absolute value of the voltage command Vq * of the inverter 42 becomes greater than the threshold value Vqref before the predetermined time tb2 has elapsed since the start of the electric travel, the absolute value of the voltage command Vq * even if the electric travel is started. Therefore, it is determined that a one-phase open failure has occurred in the inverter 42 that drives the motor MG2, and the inverter 42 is gated with the start of the engine 22 to start straight running ( Steps S170 to S180), the failure determination routine is terminated. When the failure determination routine is completed in this way, the above-described drive control (see FIG. 7) for performing the straight traveling is started.

  According to the hybrid vehicle 20B of the second embodiment described above, while the two motors MG1, MG2 are driven and traveling, the charge / discharge current Ib of the battery 50 falls outside the allowable current range, and the two When it is determined that a one-phase open failure has occurred in one of the inverters 41 and 42, the inverter 42 is controlled and the motor MG1 is driven so that only the motor MG2 is driven and electric traveling is performed. Therefore, when the one-phase open failure occurs in the inverter 41 that has performed the gate cutoff, the motor MG2 driven by the inverter 42 in which the one-phase open failure has not occurred is used. In a retreating state. Then, during the electric travel in which only the motor MG2 is driven, the absolute value of the voltage command Vq * of the inverter 42 is the threshold value Vqref until the predetermined time tb2 elapses after the electric travel is started. When larger, it is determined that a one-phase open failure has occurred in the inverter 42 that drives the motor MG2, and the voltage command Vq * of the inverter 42 is maintained until a predetermined time tb2 has elapsed since the start of electric travel. When the absolute value is less than or equal to the threshold value Vqref, it is determined that a one-phase open failure has occurred in the inverter 41 that drives the motor MG1. As a result, it is possible to determine an inverter in which a one-phase open failure has not occurred while increasing an opportunity to quickly shift to a state of traveling using a motor driven by an inverter in which a one-phase open failure has not occurred. . As a result, it is possible to increase the opportunity to suppress early charging / discharging of the battery 50 due to an excessive current due to the one-phase open failure of the inverter. Further, when it is determined that a one-phase open failure has occurred in the inverter 42 that drives the motor MG2 during the electric running in which only the motor MG2 is driven, the engine 22 is operated. Along with this, the inverter 41 is controlled so that the motor MG1 is driven to travel straight, and when it is determined that a one-phase open failure has occurred in the inverter 41 that drives the motor MG1, the electric travel is continued. Since the inverter 42 is controlled as described above, it is possible to increase the chances of shifting to a state of traveling using a motor driven by an inverter in which no one-phase open failure has occurred.

  In the hybrid vehicle 20B of the second embodiment, the torque command Tm2 * of the motor MG2 is set within the range equal to or lower than the upper limit torque Tmlim due to the upper limit vehicle speed Vlim during electric driving, but the motor MG2 has a relatively low back electromotive force. In the case of a small motor, the torque limit Tm2min, Tm2max by the input / output limits Win, Wout of the battery 50 is set without setting the torque command Tm2 * of the motor MG2 within the range of the upper limit torque Tm2lim by the upper limit vehicle speed Vlim. The torque command Tm2 * may be set within the range.

  In the hybrid vehicles 20 and 20B of the first embodiment and the second embodiment, the two motors MG1 and MG2 are driven and traveled while comparing the charge / discharge current Ib of the battery 50 with the allowable current range. Although it is determined that a one-phase open failure has occurred in one of the two inverters 41 and 42, the inverter 41 is in the middle of traveling while the two motors MG1 and MG2 are driven. , 42 may be performed by comparing a threshold value determined in advance as an experiment and the like with an absolute value of the charge / discharge current Ib of the battery 50 as a value that can be determined that a one-phase open failure has occurred. .

  In the hybrid vehicles 20 and 20B of the first and second embodiments, a one-phase open failure occurs in one of the two inverters 41 and 42 while the two motors MG1 and MG2 are being driven. When it is determined that it has occurred, the electric running is performed first, and when it is determined that a one-phase open failure has occurred in the inverter 41 during the electric running, the electric running is continued. When it is determined that a one-phase open failure has occurred in the inverter 42 while electric traveling is being performed, direct traveling is performed instead of electric traveling, but the two motors MG1 and MG2 are driven. When it is determined that a one-phase open failure has occurred in one of the two inverters 41 and 42 during traveling, the vehicle travels first straight and then travels straight. When it is determined that a one-phase open failure has occurred in the inverter 42 during the operation, the straight running is continued, and a determination is made that a one-phase open failure has occurred in the inverter 41 during the straight running. When this is done, electric travel may be performed instead of direct travel.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the one-phase open failure of the inverters 41 and 42 is determined by comparing the charge / discharge current Ib of the battery 50 and the allowable current range. Instead of the charge / discharge current Ib of the battery 50 detected by the sensor 51b, the one-phase open failure of the inverters 41 and 42 may be determined by comparing the reactor current IL detected by the current sensor 59 with the allowable current range. .

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the power from the motor MG2 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b. As illustrated in the hybrid vehicle 120 of the modification, the power from the motor MG2 is different from the axle (the axle connected to the drive wheels 63a and 63b) to which the drive shaft is connected (the wheels 64a and 64b in FIG. 12). It is good also as what outputs to the connected axle.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the two motors MG1 and MG2 that exchange electric power with the battery 50 are provided. However, three or more motors that exchange electric power with the battery 50 are provided. It may be provided. For example, as illustrated in the hybrid vehicle 220 of the modified example of FIG. 13, the power from the engine 22 is used as a drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30 with the drive of the motor MG1. In addition to the configuration that outputs to the ring gear shaft 32a and the power from the motor MG2 to the ring gear shaft 32a, an axle (drive wheels 63a and 63b) to which a drive shaft to which power from the engine 22 and the motor MG2 is output is connected. It is good also as what has motor MG3 which outputs motive power to the axle (the axle connected to wheel 64a, 64b in Drawing 13) different from the axle connected to the.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the power from the engine 22 is used as a drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30 with the drive of the motor MG1. The ring gear shaft 32a and the power from the motor MG2 are output to the ring gear shaft 32a. However, as exemplified in the hybrid vehicle 320 of the modification of FIG. 14, the first connected to the drive wheels 63a and 63b. The motor MG1 is attached to one drive shaft via the transmission 330 and the engine 22 is connected to the rotation shaft of the motor MG1 via the clutch 329. The power from the engine 22 is transmitted to the rotation shaft of the motor MG1 and the transmission 330. And outputs the power from the motor MG1 to the first drive shaft via the transmission 330. In addition to this configuration, the motor MG2 is connected to a second drive shaft (a drive shaft connected to the wheels 64a and 64b in FIG. 14) different from the first drive shaft connected to the drive wheels 63a and 63b. The power from MG2 may be output to the second drive shaft.

  In the first embodiment and the second embodiment, the present invention is applied to the hybrid vehicles 20 and 20B. However, two or more motors that can output the power required for traveling without including an engine as an internal combustion engine. It may be applied to an electric vehicle equipped with

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the motors MG1 and MG2 correspond to “motors”, the inverters 41 and 42 correspond to “inverters”, the battery 50 corresponds to “secondary batteries”, and the current connected to the positive terminal of the battery 50 The sensor 51b corresponds to the “battery current detection means”, the current sensors 45V, 45W, 46V, and 46W correspond to the “phase current detection means”, and the occurrence of the one-phase open failure based on the charge / discharge current Ib of the battery 50 is detected. Determination is made to perform electric traveling, and during the electric traveling, it is determined whether one-phase open failure has occurred in either inverter 41 or 42 based on charge / discharge current Ib of battery 50 or voltage command Vq * of inverter 42. The failure determination routine of FIG. 3 or the failure determination routine of FIG. 9 and the torque command Tm2 * of the motor MG2 are set in order to perform electric running. The electric travel drive control routine of FIG. 4 or the electric travel drive control routine of FIG. 10 transmitted to the motor ECU 40 together with the gate cutoff command of the motor 41, and the torque command Tm1 * of the motor MG1 for setting the direct travel, the inverter 42 The hybrid electronic control unit 70 that executes the direct drive control routine of FIG. 7 that is transmitted to the motor ECU 40 together with the gate cutoff command of the engine, the engine ECU 24 that controls the operation of the engine 22 in response to the operation stop command, and the torque command Tm1 * The combination with the motor ECU 40 that controls the inverters 41 and 42 so that the motor MG1 and the motor MG2 are driven in response to the torque command Tm2 * corresponds to the “determination control means”. The engine 22 corresponds to an “internal combustion engine”, the power distribution and integration mechanism 30 corresponds to a “planetary gear mechanism”, and the current sensor 59 that detects the reactor current IL also corresponds to “battery current detection means”.

  Here, the “motor” is not limited to the motors MG1 and MG2 as the synchronous generator motor, and may be a plurality of motors that are driven by three-phase AC and can output the power required for traveling, such as an induction motor. It does not matter as long as it is anything. The “inverter” is not limited to the inverters 41 and 42, and any inverter may be used as long as it has a plurality of switching elements and drives a plurality of motors. The “secondary battery” is not limited to the battery 50 configured as a lithium ion secondary battery, and a plurality of the “secondary batteries” are provided via a plurality of inverters such as a nickel hydride secondary battery, a nickel cadmium secondary battery, and a lead storage battery. Any type of secondary battery may be used as long as it can exchange power with the motor. The “battery current detection means” is not limited to the current sensor 51b or the current sensor 59, and any battery current detection means may be used as long as it detects a battery current that is a current for charging / discharging the secondary battery. The “phase current detection means” is not limited to the current sensors 45V, 45W, 46V, and 46W, but flows in each phase of a plurality of motors, including those that detect the U-phase current of the motor. Any device can be used as long as it can detect the phase current. The “determination control means” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. Further, the “determination control means” determines whether a one-phase open failure has occurred based on the charging / discharging current Ib of the battery 50, performs electric traveling, and performs charging / discharging current Ib of the battery 50 or an inverter during electric traveling. Based on the voltage command Vq * of 42, it is determined which one of the inverters 41, 42 has a one-phase open failure, or the torque command Tm2 of the motor MG2 for electric running or the gate cutoff command of the inverter 42 Accordingly, the inverter 42 is not limited to the one that controls the inverter 41 according to the torque command Tm1 * of the motor MG1 or the gate cutoff command of the inverter 41 for performing the straight traveling. One of a plurality of inverters based on the battery current detected while the motor is driven When it is determined that an off abnormality has occurred in which a part of the plurality of switching elements cannot be turned on from off, a plurality of motors are driven so that only a predetermined motor that is a part of the plurality of motors is driven. Among the inverters, the inverter that drives a predetermined motor is controlled and the gate of an inverter different from the inverter that drives the predetermined motor is cut off, and the battery current detected while only the predetermined motor is driven or traveling is Any device may be used as long as it determines whether or not an off abnormality has occurred in the inverter that drives the predetermined motor based on the detected phase current. Further, the “internal combustion engine” is not limited to the engine 22 as an internal combustion engine that outputs power by a hydrocarbon-based fuel such as gasoline or light oil, and is any type of internal combustion engine such as a hydrogen engine. It doesn't matter. The “planetary gear mechanism” is not limited to the power distribution and integration mechanism 30; an output shaft of the internal combustion engine, a rotation shaft of a first motor that is one of a plurality of motors, and a drive shaft connected to the axle. As long as three rotating elements are connected to the three axes, any configuration may be used.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of electric vehicles.

  20, 20B, 120, 220, 320 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution and integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 Pinion gear, 34 carrier, 35 reduction gear, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 45V, 45W, 46V, 46W, 51b, 59 current sensor, 50 battery, 51a, 57a, 58a Voltage sensor, 51c Temperature sensor, 52 Electronic control unit for battery (battery ECU), 54, 56 Power line, 55 Boost converter, 57, 58 Capacitor, 60 Gear mechanism, 62 differential Shall gear, 63a, 63b drive wheel, 64a, 64b wheel, 70 hybrid electronic control unit, 72 CPU, 74 ROM, 76 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position Sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 329 clutch, 330 transmission, D11 to D16, D21 to D26, D31, D32 diode, L reactor, MG1, MG2, MG3 motor, T11 to T16, T21 to T26, T31, T32 transistors.

Claims (7)

A plurality of motors driven by three-phase alternating current and capable of outputting power required for traveling, a plurality of inverters each having a plurality of switching elements and driving the plurality of motors, and the plurality of inverters via the plurality of inverters An electric vehicle comprising a secondary battery capable of exchanging electric power with the motor of
Battery current detecting means for detecting a battery current which is a current for charging and discharging the secondary battery;
Phase current detection means for detecting a phase current flowing in each phase of the plurality of motors;
An off state in which a part of the plurality of switching elements cannot be turned on from any of the plurality of inverters based on the detected battery current while the plurality of motors are driven to travel. When it is determined that an abnormality has occurred, an inverter that drives the predetermined motor among the plurality of inverters is controlled so that only a predetermined motor that is a part of the plurality of motors is driven to travel. In addition, the gate of an inverter different from the inverter that drives the predetermined motor is cut off, and only the predetermined motor is driven and running while the detected battery current or the detected phase current is Determination control means for determining whether or not the off abnormality has occurred in an inverter that drives a predetermined motor;
An electric vehicle comprising: The electric vehicle according to claim 1,
The determination control means charges / discharges the secondary battery by the detected battery current until a predetermined time elapses after the control is started so that only the predetermined motor is driven to run. When it is out of the allowable current range set as the allowable range in the determination, it is determined that the off abnormality has occurred in the inverter that drives the predetermined motor, and the detected battery current is within the allowable current range. It is means for determining that the off abnormality has occurred in an inverter different from an inverter that drives the predetermined motor among the plurality of inverters when it is not outside.
Electric vehicle. The electric vehicle according to claim 1,
The plurality of inverters are commands obtained by feedback control using a proportional term and an integral term so that the detected phase current has a value corresponding to a torque command to be output from the motor for each of the motors driven. Can be controlled by value,
The determination control means is configured such that an inverter that drives the predetermined motor is controlled by the command value and starts control so that only the predetermined motor is driven to run and a predetermined time elapses. When the absolute value of the command value in the feedback control is outside the allowable value range set as the allowable range when charging and discharging the secondary battery, the off abnormality occurs in the inverter that drives the predetermined motor. When the absolute value of the command value does not fall outside the allowable value range, it is determined that the off abnormality has occurred in an inverter different from the inverter that drives the predetermined motor among the plurality of inverters. Is a means to
Electric vehicle. The electric vehicle according to claim 3,
The predetermined motor is a motor whose rotational speed increases as the vehicle speed increases,
The plurality of inverters are configured so that only the predetermined motor is driven and travels within a range in which the vehicle speed is equal to or lower than a preset upper limit vehicle speed during traveling while only the predetermined motor is driven. Is a means of controlling
Electric vehicle. An electric vehicle according to any one of claims 1 to 4,
The determination control means has a second tolerance set as a range in which the detected battery current is allowed when the secondary battery is charged and discharged while the plurality of motors are driven to travel. It is means for determining that the off abnormality has occurred in any of the plurality of inverters when it is outside the current range.
Electric vehicle. An electric vehicle according to any one of claims 1 to 5,
When the determination control means determines that the off abnormality has occurred in the inverter that drives the predetermined motor while only the predetermined motor is being driven, the determination control means includes the plurality of motors. The plurality of inverters are controlled so that only a motor different from the predetermined motor is driven to travel, and it is determined that the off abnormality has occurred in an inverter different from the inverter driving the predetermined motor among the plurality of inverters. When it does, it is means for controlling the plurality of inverters so as to continue running with only the predetermined motor being driven,
Electric vehicle. An electric vehicle according to any one of claims 1 to 6,
An internal combustion engine;
A planetary gear mechanism in which three rotating elements are connected to three axes of an output shaft of the internal combustion engine, a rotating shaft of a first motor that is one of the plurality of motors, and a driving shaft connected to an axle;
With
A second motor, which is the remaining one of the plurality of motors, is connected to the drive shaft;
Electric vehicle.

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