JP5733004B2 - Hybrid car - Google Patents

Description

  The present invention relates to a hybrid vehicle, and more specifically, an internal combustion engine that can output power for traveling, a first motor that can generate electric power using power from the internal combustion engine, a first inverter that drives the first motor, A second motor capable of outputting power for traveling, a second inverter for driving the second motor, a secondary battery, and the first motor and the second motor via the first inverter and the second inverter. And a relay connected to the hybrid vehicle.

  Conventionally, as a technology applicable to this type of electric vehicle such as a hybrid vehicle, a traveling motor, an inverter that drives the motor, an auxiliary device such as an air compressor, a battery, and the battery can be separated from the inverter side. Electric vehicle comprising a voltage waveform output circuit for outputting a voltage waveform corresponding to an insulation resistance in a power system, including a system main relay, and a relay capable of disconnecting an auxiliary machine from a power line connecting the inverter and the system main relay , When the ignition is turned on, a decrease in the insulation resistance of the power system is detected based on the voltage waveform from the voltage waveform output circuit, and when the ignition is subsequently turned off, the insulation resistance of the power system is decreased. The thing which specifies the site | part in which this occurred is proposed (for example, refer patent document 1). In this electric vehicle, when specifying the part where the insulation resistance is lowered, the insulation resistance is lowered from the inverter to the motor side based on the voltage waveform from the voltage waveform output circuit when the inverter is turned off, for example. Or whether it is present or not.

JP 2008-29165 A

  However, in the above-described electric vehicle, there may be a case where the part where the insulation resistance is reduced cannot be specified. For example, even if a short circuit occurs in the insulation film of the power line or signal line, and a decrease in insulation resistance is detected during the running of the vehicle, the voltage waveform is caused by the vibration of the vehicle for a while after that. When the voltage waveform from the output circuit temporarily returns to normal, and the vehicle is stopped and the ignition is turned off, the voltage waveform from the voltage waveform output circuit cannot identify the location where the insulation resistance has decreased. There are cases where

  The main purpose of the hybrid vehicle of the present invention is to more reliably identify the part where the insulation resistance is reduced.

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

The hybrid vehicle of the present invention
An internal combustion engine capable of outputting traveling power, a first electric motor capable of generating electric power using the power from the internal combustion engine, a first inverter driving the first electric motor, and a first inverter capable of outputting traveling power Two motors, a second inverter that drives the second motor, a secondary battery, and the secondary battery is connected to the first motor and the second motor via the first inverter and the second inverter. A hybrid vehicle comprising a relay,
Insulation of an electric system comprising a part or all of a plurality of parts including the first electric motor, the second electric motor, and the secondary battery according to the states of the first inverter, the second inverter, and the relay. Insulation resistance signal detecting means for detecting an insulation resistance signal according to the resistance;
The relay is turned on when the portion of the plurality of portions where the decrease in insulation resistance has occurred after the decrease in the insulation resistance of the electrical system is detected based on the detected insulation resistance signal. (2) driving the first internal motor with the inverter shut off and driving the first motor to drive with a driving force based on a required driving force required for driving; and turning on the relay. A second motor running that drives the second motor with a driving force based on the required driving force in a state where the operation of the internal combustion engine is stopped and the first inverter is shut off, and the internal combustion engine And driving the first motor and the second motor to drive the secondary battery without charging / discharging and running with a driving force based on the required driving force, respectively, When the internal combustion engine, the first inverter, the second inverter, and the relay are controlled so that the first electric motor traveling, the second electric motor traveling, and the non-charge / discharge traveling are performed, respectively. Insulation resistance lowering part specifying means for specifying a part of the plurality of parts where a decrease in insulation resistance occurs based on an insulation resistance signal detected by the insulation resistance signal detecting means;
It is a summary to provide.

  In the hybrid vehicle of the present invention, the first inverter that drives the first motor that can generate power using the power from the internal combustion engine that can output the driving power, and the second motor that can output the driving power. The first motor, the second motor, and the secondary according to each state of the second inverter to be driven and the relay that connects the secondary battery to the first motor and the second motor via the first inverter and the second inverter An insulation resistance signal corresponding to an insulation resistance of an electric system composed of a part or all of a plurality of parts including a battery is detected. Then, the relay is turned on and the second inverter is turned on when the portion where the decrease in the insulation resistance has occurred among the plurality of portions after the decrease in the insulation resistance of the electric system is detected based on the detected insulation resistance signal. The first electric motor traveling with the driving force based on the required driving force required for traveling by driving the first electric motor while the gate is shut off and the operation of the internal combustion engine with the relay turned on Is stopped and the second inverter is driven with the first inverter driven and the second motor is driven by the driving force based on the required driving force, the internal motor is operated and the first motor and the second motor are driven. An internal combustion engine, a first inverter, and a second inverter so that non-charging / discharging traveling by driving power based on the required driving force without charging and discharging the secondary battery by driving an electric motor is performed, respectively. The insulation resistance of the plurality of parts is reduced based on the insulation resistance signal detected when the first motor running, the second motor running, and the non-charge / discharge running are performed by controlling the relay. Identify the site. Therefore, it is determined whether or not the insulation resistance has decreased in the portion closer to the second motor than the second inverter by running the first motor, or more than the first inverter by running the second motor. It is determined whether or not a decrease in insulation resistance has occurred in a portion on the first motor side, or whether or not a decrease in insulation has occurred in a portion closer to the secondary battery than the relay by performing non-charge / discharge running. Therefore, it is possible to perform a process for specifying a portion where the insulation resistance has decreased during traveling. As a result, it is possible to more reliably identify the part where the insulation resistance is reduced.

In such a hybrid vehicle of the present invention, the insulation resistance lowering portion specifying means includes the insulation resistance signal detected by the insulation resistance signal detection means when the first motor is running and the state of the first motor running . Based on the insulation resistance signal detected by the insulation resistance signal detection means when the second inverter is operated so that the gate interruption of the second inverter is released and torque is not output from the second motor. Insulation resistance detected by the insulation resistance signal detection means when the second motor is running is determined by determining whether or not a decrease in insulation resistance has occurred in a portion closer to the second motor than the second inverter. torque from the signal and the second electric motor to release the gate cut off from the state of the first inverter traveling the first electric motor is not output Whether or not there is a decrease in insulation resistance at a portion closer to the first motor than the first inverter based on an insulation resistance signal detected by the insulation resistance signal detection means when the first inverter is operated. And the secondary battery side from the relay based on an insulation resistance signal detected by the insulation resistance signal detection means when the relay is turned from on to off when the non-charge / discharge running is performed. It can also be a means for determining whether or not a decrease in insulation resistance has occurred in this part. If it carries out like this, the site | part where the fall of the insulation resistance can be identified more appropriately.

  Further, in the hybrid vehicle of the present invention, the insulation resistance lowering part specifying means is an insulation resistance detected by the insulation resistance signal detecting means when switching from running with the operation of the second inverter to running of the first electric motor. When it is determined whether or not a decrease in insulation resistance has occurred in a portion of the second motor side from the second inverter based on the signal, and when the traveling with the operation of the first inverter is switched to the second motor traveling The insulation resistance signal detected by the insulation resistance signal detection means determines whether a decrease in insulation resistance has occurred in the first motor side of the first inverter, and the uncharged / discharged travel is performed. When the relay is turned from on to off, the relay is detected based on the insulation resistance signal detected by the insulation resistance signal detection means. A means for determining whether the reduction in the insulation resistance more sites of the secondary battery side is occurring, may be a thing. If it carries out like this, the site | part where the fall of the insulation resistance can be identified more appropriately.

  Furthermore, in the hybrid vehicle of the present invention, the drive voltage system in which the first inverter and the second inverter are connected by boosting the power supplied via the relay from the battery voltage system to which the secondary battery is connected. The first motor and the second motor are motors that generate a counter electromotive voltage when rotated, and the insulation resistance lowering portion specifying means is configured to output the voltage of the drive voltage system, The counter electromotive voltage generated by the rotation of the first motor and the counter electromotive voltage generated by the rotation of the second motor are set to be equal to or higher than a predetermined voltage determined as a voltage capable of suppressing the influence on the insulation resistance signal. In the state, the internal combustion engine, the first inverter, the second inverter, the relay, and the relay so that the first electric motor traveling and the second electric motor traveling are performed. A means for controlling the pressure converter can also be a thing. In this way, the back electromotive voltage generated by the rotation of the first motor and the back electromotive voltage generated by the rotation of the second motor are insulated as compared with the one that allows the voltage of the drive voltage system to be less than the predetermined voltage. The influence on the resistance signal can be suppressed. As a result, a decrease in insulation resistance can be detected more appropriately. In this case, the predetermined voltage includes the back electromotive voltage according to the rotation speed of the first motor generated by the rotation of the first motor when the second motor travel is performed and the first motor travel. It is also possible that the voltage is determined to be larger than the larger one of the counter electromotive voltage according to the rotation speed of the second motor generated by the rotation of the second motor. In this case, the predetermined voltage may be a maximum value of the voltage of the drive voltage system that can be boosted by the boost converter. By doing so, it is possible to more reliably suppress the influence of the counter electromotive voltage generated by the rotation of the first motor and the counter electromotive voltage generated by the rotation of the second motor on the insulation resistance signal.

  Alternatively, in the hybrid vehicle of the present invention, the insulation resistance lowering portion specifying means controls the first electric motor running and the second electric motor running so as to perform the non-charge / discharge running. It can also be. In this way, the system can be stopped without switching the relay from OFF to ON when an instruction to stop the system is given during non-charge / discharge running. As a result, it is possible to suppress inconveniences caused by turning on the relay during traveling.

  The hybrid vehicle of the present invention further includes 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 the first electric motor, and a driving shaft connected to the axle, The second electric motor may be connected to the drive shaft.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is a block diagram which shows the outline of a structure of the electric system of an Example. It is a flowchart which shows an example of the insulation resistance fall detection processing routine performed by the electronic control unit for hybrid 70 of an Example. It is a flowchart which shows an example of the insulation resistance fall site | part specific process routine performed by the hybrid electronic control unit 70 of an Example. It is a flowchart which shows an example of the drive control routine for insulation resistance fall site | part specification performed by the electronic control unit for hybrids 70 of an 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 between the rotation speed and torque in the rotation element of the planetary gear 30 at the time of drive | working in the orthogonal drive mode. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the planetary gear 30 when drive | working by electric drive mode. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, the target rotational speed Ne *, and the target torque Te * are set. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the planetary gear 30 at the time of drive | working by batteryless drive mode. 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 configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as one embodiment of the present invention, and FIG. 2 is a configuration diagram showing an outline of the configuration of an electric system included in the hybrid vehicle 20. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22 that uses gasoline or light oil as fuel, an engine electronic control unit (hereinafter referred to as engine ECU) 24 that controls the drive of the engine 22, and a crank of the engine 22. A planetary gear 30 in which a carrier is connected to the shaft 26 and a ring gear is connected to the drive shaft 32 connected to the drive wheels 39a and 39b via a differential gear 38, and a rotor is configured as a synchronous generator motor, for example. A motor MG1 connected to the sun gear, a motor MG2 configured as a synchronous generator motor and having a rotor connected to the drive shaft 32, inverters 41 and 42 for driving the motors MG1 and MG2, and inverters 41, 42 is controlled by switching control. A motor electronic control unit (hereinafter referred to as a motor ECU) 40 for driving and controlling the motors MG1 and MG2, a battery 50 configured as a secondary battery such as a lithium ion secondary battery, and a battery electronic for managing the battery 50 A control unit (hereinafter referred to as a battery ECU) 52, a power line (hereinafter referred to as a high voltage system power line) 54a to which inverters 41 and 42 are connected, and a power line (to which a battery 50 is connected via a system main relay 56) The voltage VH of the high voltage system power line 54a is adjusted within the range from the voltage VL of the battery voltage system power line 54b to the maximum allowable voltage VHmax and is connected to the battery voltage system power line 54b). Booster that exchanges power between the line 54a and the battery voltage system power line 54b Converter 55, a smoothing capacitor 57 connected to the positive and negative buses of high voltage system power line 54a, and a smoothing capacitor 58 connected to the positive and negative buses of battery voltage system power line 54b. An air conditioner 60 that performs air conditioning in the passenger compartment, an inverter 62 that is connected to the battery voltage system power line 54b and drives the air conditioning compressor 61 of the air conditioner 60, a negative terminal of the battery 50, and the system main relay 56 A voltage waveform that is connected to a connection point Cn (see FIG. 2) and outputs a voltage waveform corresponding to an insulation resistance of a current connection part (hereinafter referred to as a current connection part) as viewed from the connection point Cn in the electric system. An output circuit 90 and a hybrid electronic control unit 70 that controls the entire vehicle are provided.

  Each of the motor MG1 and the motor MG2 is configured as a known synchronous generator motor including a rotor in which a permanent magnet is embedded and a stator around which a three-phase coil is wound. As shown in FIG. 2, the inverters 41 and 42 include six transistors T11 to T16 and T21 to 26, and six diodes D11 to D16 and D21 connected in parallel to the transistors T11 to T16 and T21 to T26 in the reverse direction. D26. Two transistors T11 to T16 and T21 to T26 are arranged in pairs so as to be on the source side and the sink side with respect to the positive and negative buses of the high voltage power line 54a, respectively. The three-phase coils (U-phase, V-phase, W-phase) of the motors MG1, MG2 are connected to the connection points. Therefore, the three-phase coil is controlled by controlling the on-time ratios of the transistors T11 to T16 and T21 to T26 that are paired in a state in which a voltage is applied between the positive electrode bus and the negative electrode bus of the high voltage power line 54a. Thus, a rotating magnetic field can be formed, and the motors MG1 and MG2 can be driven to rotate.

The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, for example, rotation of the rotors of the motors MG1 and MG2 from a rotational position detection sensor (not shown) that detects the rotational position of the rotors of the motors MG1 and MG2. The position, the phase current applied to the motors MG1 and MG2 detected by a current sensor (not shown), the inverter temperature from a temperature sensor (not shown) attached to the inverters 41 and 42, and the like are input. Switching control signals to the transistors T11 to T16 and T21 to 26 of the inverters 41 and 42 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
Calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions of the rotors of the motors MG1 and MG2 from a rotational position detection sensor (not shown).

  As shown in FIG. 2, the boost converter 55 is configured as a boost converter including two transistors T31 and T32, two diodes D31 and D32 connected in parallel to the transistors T31 and T32 in a reverse direction, and a reactor L. . The two transistors T31 and T32 are respectively connected to the positive bus of the high voltage system power line 54a and the negative bus of the high voltage system power line 54a and the battery voltage system power line 54b, and the reactor L is connected to the connection point. Has been. Further, the positive terminal and the negative terminal of the battery 50 are connected to the reactor L and the negative bus of the battery voltage system power line 54b via the system main relay 56, respectively. Therefore, by turning on / off the transistors T31 and T32, the power of the battery voltage system power line 54b is boosted and supplied to the high voltage system power line 54a, or the power of the high voltage system power line 54a is reduced to reduce the battery voltage. Or can be supplied to the system power line 54b.

  In the battery ECU 52, signals necessary for managing the battery 50, for example, voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, battery voltage system power connected to the output terminal of the battery 50 A charge / discharge current from a current sensor (not shown) attached to the line 54b, a battery temperature from a temperature sensor (not shown) 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. In addition, the battery ECU 52 manages the battery 50, and the power storage that is the ratio of the stored power amount stored in the battery 50 based on the integrated value of the charge / discharge current detected by the current sensor to the total capacity (power storage capacity). The 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.

  As shown in FIG. 2, the inverter 62 includes six transistors T41 to T46 and six diodes D41 to D46 connected in parallel to the transistors T41 to T46 in the reverse direction. That is, the inverter 62 is configured in the same manner as the inverters 41 and 42 described above except that the inverter 62 is connected to the battery voltage system power line 54b instead of the high voltage system power line 54a.

  As shown in FIG. 2, the voltage waveform output circuit 90 is connected to an oscillator 92 that is grounded and generates a pulse of a constant frequency (for example, a rectangular wave, a sine wave, a triangular wave, etc.), and one terminal is connected to the oscillator 92. The detection resistor 94, the capacitor 95 connected to the other terminal of the detection resistor 94 and the connection point Cn, and the connection point Co between the detection resistor 94 and the capacitor 95 are connected to the high frequency component to remove the signal. A low-pass filter 96 that outputs to the hybrid electronic control unit 70, and outputs a signal (voltage waveform) to the hybrid electronic control unit 70 in accordance with the relationship between the resistance value of the detection resistor 94 and the resistance value of the current connection portion described above. Output. The voltage waveform from the voltage waveform output circuit 90 is a voltage waveform having substantially the same amplitude as that of the oscillator 92 when the insulation resistance of the current connection portion is not reduced (when there is no risk of leakage), When the insulation resistance is lowered (when there is a risk of leakage), a voltage waveform having a smaller amplitude than that of the oscillator 92 is generated due to a voltage drop at the detection resistor 94. Therefore, in the electronic control unit 70 of the embodiment, the amplitude of the voltage waveform from the voltage waveform output circuit 90 is the amplitude of the voltage waveform of the oscillator 92 as an insulation determination for determining whether or not the insulation resistance at the current connection site is normal. It is determined that the insulation resistance of the current connection site is normal when it is equal to or greater than the threshold for determination determined as a slightly smaller value, and the insulation resistance of the current connection site when the voltage waveform from the voltage waveform output circuit 90 is smaller than the threshold for determination. Is determined to be lowered (abnormal).

  Here, the present connection part seen from the connection point Cn in the electric system is the motors MG1, MG2 and the air conditioning compressor 61, according to the states of the inverters 41, 42, the inverter 62, and the system main relay 56 in the embodiment. It consists of a part or all of a plurality of parts including the battery 50. When the system main relay 56 is on and the motors MG1 and MG2 are driven by the drive of the inverters 41 and 42 and the air conditioning compressor 61 is driven by the drive of the inverter 62 (hereinafter referred to as full drive). The current connection portion includes all of the motors MG1 and MG2, the inverters 41 and 42, the air conditioning compressor 61, the inverter 62, the system main relay 56, and the battery 50. For example, when the gate of the inverter 41 is cut off during full driving, the current connection part is a state where the part of the motor MG1 side from the inverter 41 (hereinafter referred to as the first motor area) is removed from the state of full driving. Sometimes, when the inverter 42 is gate-cut off, the current connection part is a state where the part of the motor MG2 side (hereinafter referred to as the second motor area) is removed from the inverter 42 from the state of full drive, and the inverter 62 is When the gate is shut off, the current connection portion is a portion obtained by excluding a portion on the air conditioning compressor 61 side (hereinafter referred to as an air conditioner area) from the inverter 62 from the state of all driving. Further, when the system main relay 56 is turned off, the current connection portion is a portion closer to the battery 50 than the system main relay 56 (hereinafter referred to as a battery area). In addition, each area, such as a 1st motor area, a 2nd motor area, an air-conditioner area, and a battery area, is insulated mutually independently.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72. In addition to the CPU 72, a ROM 74 that stores a processing program, a RAM 76 that temporarily stores data, and a non-volatile that holds the stored data. Flash memory 78 and an input / output port and a communication port (not shown). In the hybrid electronic control unit 70, the voltage of the capacitor 57 (the voltage of the high voltage system power line 54 a) VH from the voltage sensor 57 a attached between the terminals of the capacitor 57 and the voltage sensor attached between the terminals of the capacitor 58. The voltage of the capacitor 58 from 58a (the voltage of the battery voltage system power line 54b) VL, the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever, and the depression amount of the accelerator pedal Accelerator opening degree Acc from the accelerator pedal position sensor 84 for detecting the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal, the vehicle speed V from the vehicle speed sensor 88, and a voltage waveform output circuit Such as a signal from 0 (voltage waveform) is input via the input port. From the hybrid electronic control unit 70, a switching control signal to the transistors T31 and T32 of the boost converter 55, an on / off signal to the system main relay 56, a switching control signal to the transistors T41 to T46 of the inverter 62, and a warning lamp 89 A lighting signal or the like is output via the output port. As described above, the hybrid electronic control unit 70 also determines whether or not the insulation resistance of the current connection portion is normal. 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. Is doing.

  The hybrid vehicle 20 of the embodiment configured in this way calculates the required torque to be output to the drive shaft 32 based on the accelerator opening Acc and the vehicle speed V corresponding to the amount of depression of the accelerator pedal 83 by the driver. The operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the torque is output to the drive shaft 32. As the 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 transmitted to the planetary gear 30 and the motor MG1. And the motor MG2 convert the torque and output to the drive shaft 32. The torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 and the power suitable for the sum of the required power and the power required for charging and discharging the battery 50 are obtained. The operation of the engine 22 is controlled so as to be output from the engine 22, and all or a part of the power output from the engine 22 with charging / discharging of the battery 50 is converted by the planetary gear 30, the motor MG1, and the motor MG2. Accordingly, the required power is output to the drive shaft 32. Charge-discharge drive mode for driving and controlling the motor MG1 and the motor MG2, there is a motor operation mode in which operation control to output a power commensurate to stop the operation of the engine 22 to the required power from the motor MG2 to the drive shaft 32. Both the torque conversion operation mode and the charge / discharge operation mode are modes in which the engine 22 and the motors MG1, MG2 are controlled so that the required power is output to the drive shaft 32 with the operation of the engine 22. Can be considered as an engine operation mode.

  In addition, in the hybrid vehicle 20 of the embodiment, in addition to the normal driving modes such as the engine operation mode and the motor operation mode, a plurality of retreat driving modes are prepared in advance for when the vehicle is abnormal. As a mode for the retreat travel, the engine 22 is operated at a predetermined rotation speed while the inverter 42 for driving the motor MG2 is shut off, and a part of the power output from the engine 22 is transmitted to the planetary gear 30 and the motor MG1. A straight running mode in which the engine 22 and the motor MG1 are controlled so that power based on the requested power is output to the drive shaft 32 with torque conversion by the inverter, and an inverter for stopping the operation of the engine 22 and driving the motor MG1 An electric running mode for controlling the motor MG2 so that power based on the requested power from the motor MG2 is output to the drive shaft 32 with the gate 41 shut off, and output from the engine 22 in a state where charging / discharging of the battery 50 is prohibited. From power to power conversion and power by the motors MG1 and MG2 A battery that controls the engine 22 and the motors MG1 and MG2 so that power based on the required power is output to the drive shaft 32 with charge and discharge of the capacitor 57 within the capacity range of the capacitor 57. There are less driving modes.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly, the operation when the portion of the electric system where the decrease in the insulation resistance has occurred after the decrease in the insulation resistance in the electric system is detected will be described. To do. FIG. 3 is a flowchart showing an example of an insulation resistance lowering detection processing routine executed by the hybrid electronic control unit 70, and FIG. 4 shows an example of an insulation resistance lowering part specifying processing routine executed by the hybrid electronic control unit 70. FIG. 5 is a flowchart illustrating an example of the drive control routine for specifying the insulation resistance lowering portion executed by the hybrid electronic control unit 70. The routine of FIG. 3 and the routine of FIG. 4 are executed when the system main relay 56 is turned on by ignition ON and the vehicle is activated. The routine of FIG. 5 is executed when the mode for retreat travel is set by the routine of FIG. Hereinafter, for convenience of explanation, first, drive control for specifying an insulation resistance lowering portion will be described, then an insulation resistance lowering detection process will be described, and then an insulation resistance lowering portion specifying process will be described.

  When the drive control routine for specifying the insulation resistance lowering portion shown in FIG. 5 is executed, the hybrid electronic control unit 70 first starts the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, and the motor MG1. , MG2 rotation speeds Nm1, Nm2, input / output limits Win and Wout of the battery 50, a mode for retreat travel, and the like, a process of inputting data necessary for control is executed (step S400). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by a rotational position detection sensor (not shown). It was supposed to be. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature of the battery 50 and the storage ratio SOC of the battery 50, and are input from the battery ECU 52 by communication. Further, the mode set for retreat travel is input by the mode set by the insulation resistance lowering portion specifying process routine of FIG. 4 to be described later.

  When the data is input in this way, the required torque Tr * to be output to the drive shaft 32 connected to the drive wheels 39a and 39b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V, and the engine 22 The required required power Pe * is set (step S410). 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. 6 shows an example of the required torque setting map. The required power Pe * can be calculated as the sum of the set required torque Tr * multiplied by the rotational speed Nr of the drive shaft 32 and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. The rotational speed Nr of the drive shaft 32 can be obtained by multiplying the vehicle speed V by a conversion coefficient k (Nr = k · V), or the rotational speed Nm2 of the motor MG2 can be used.

  Subsequently, the input mode for retreat travel is checked (step S420), and when the direct travel mode is set as the retreat travel mode, the system main relay 56 is kept on (step S430). A predetermined rotational speed Neset, which is predetermined as a rotational speed greater than the idle rotational speed, is set as the target rotational speed Ne * at which the engine 22 is to be operated (step S440).

  Next, a temporary torque Tm1tmp, which is a temporary value of torque to be output from the motor MG1, is calculated by the following equation (1) obtained by multiplying the required torque Tr * by the product of the gear ratio ρ of the planetary gear 30 and the value −1 ( In step S450), torque limits Tm1min and Tm1max as upper and lower limits of the 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 rotational speed Nm1 of the motor MG1 (step S460). The calculated temporary torque Tm1tmp is limited by the torque limits Tm1min and Tm1max according to the equation (2), and the torque command Tm1 * of the motor MG1 is set (step S470). 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. FIG. 7 shows an example of a collinear diagram showing the dynamic relationship between the rotational speed and torque of the rotating elements of the planetary gear 30 when traveling in the straight traveling mode. In the figure, the left S-axis indicates the rotational speed of the sun gear, which is the rotational speed Nm1 of the motor MG1, the C-axis indicates the rotational speed of the carrier, which is the rotational speed Ne of the engine 22, and the R-axis indicates the rotational speed Nm2 of the motor MG2. The rotational speed Nr of the drive shaft 32 is shown. Further, in the figure, a thick arrow on the R axis indicates a torque that the torque Tm1 output from the motor MG1 acts on the drive shaft 32. Note that Equation (1) for calculating the temporary torque Tm1tmp of the motor MG1 can be easily derived by using this alignment chart.

Tm1tmp = -ρ ・ Tr * (1)
Tm1 * = max (min (Tm1tmp, Tm1max), Tm1min) (2)

  When the target rotational speed Ne * of the engine 22 and the torque command Tm1 * of the motor MG1 are set in this manner, the set target rotational speed Ne * of the engine 22 is transmitted to the engine ECU 24 and the set torque command Tm1 * of the motor MG1 and the motor A gate cutoff command for inverter 42 that drives MG2 is transmitted to motor ECU 40 (step S480), and the insulation resistance lowering portion specifying drive control routine is terminated. 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. The motor ECU 40 that has received the gate cutoff command of the inverter 42 and the torque command Tm1 * of the motor MG1 sets the transistors T11 to T16 of the inverter 41 so that the motor MG1 is driven by the torque command Tm1 * with the inverter 42 gated off. Perform switching control. The engine ECU 24 that has received the target rotational speed Ne * while the operation of the engine 22 is stopped cranks the engine 22 by the motoring torque from the motor MG1 set using a predetermined torque map. In addition, the engine 22 is started by starting fuel injection and ignition when the rotational speed Ne of the engine 22 reaches a predetermined ignition start rotational speed, and the rotational speed Ne is set to the target rotational speed Ne after the engine 22 is started. Start operation control such as intake air amount control, fuel injection control, and ignition control so as to become *. By such control, the engine 22 can receive the torque from the motor MG1 within the range of the input / output limits Win and Wout of the battery 50, thereby outputting the required torque Tr * to the drive shaft 32 and traveling.

  When it is determined in step S420 that the electric travel mode is set, the system main relay 56 is kept on (step S490), and the required torque Tr * is a temporary value to be output from the motor MG2. Is set to the temporary torque Tm2tmp (step S500), and the input / output limits Win and Wout of the battery 50 are divided by the rotational speed Nm2 of the motor MG2, thereby limiting the torque as the upper and lower limits of the torque that may be output from the motor MG2. Tm2min and Tm2max are calculated (step S510), and the calculated temporary torque Tm2tmp is limited to the torque limit Tm2min and Tm2max by the following equation (3) to set the torque command Tm2 * of the motor MG2 (step S520).

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

  When the torque command Tm2 * of the motor MG2 is set in this way, the operation stop command of the engine 22 is transmitted to the engine ECU 24, and the gate cutoff command of the inverter 41 for driving the motor MG1 and the set torque command Tm2 * of the motor MG2 are set. It transmits to motor ECU40 (step S530), and the insulation resistance fall site | part drive control routine is complete | finished. The engine ECU 24 that receives the operation stop command for the engine 22 stops operation control such as intake air intake amount control, fuel injection control, and ignition control of the engine 22 when the engine 22 is operating. The motor ECU 40 that has received the gate cutoff command of the inverter 41 and the torque command Tm2 * of the motor MG2 sets the transistors T21 to T26 of the inverter 42 so that the motor MG2 is driven by the torque command Tm2 * with the inverter 41 gated off. Perform switching control. By such control, it is possible to travel by outputting the required torque Tr * from the motor MG2 to the drive shaft 32 within the range of the input / output limits Win and Wout of the battery 50. FIG. 8 shows an example of a collinear diagram showing the dynamic relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when traveling in the electric travel mode. In the figure, a thick arrow on the R axis indicates the torque Tm2 output from the motor MG2 to the drive shaft 32.

  When it is determined in step S420 that the battery-less travel mode is set, the system main relay 56 is kept on (step S440), and the engine 22 should be operated based on the set required power Pe *. A target rotational speed Ne * and a target torque Te * are set (step S450). This setting is performed based on an operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 9 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Subsequently, the torque to be output for receiving the torque from the engine 22 by the motor MG1 using the gear ratio ρ of the planetary gear 30 is set as the torque command Tm1 * of the motor MG1 by the following equation (4) (step S460). , Multiplying the set torque command Tm1 * by the rotational speed Nm1 of the motor MG1 to calculate electric power Pm1 generated or consumed by the motor MG1 (step S470), and dividing the calculated electric power Pm1 by the rotational speed Nm2 of the motor MG2 Is set as a torque command Tm2 * of the motor MG2 (step S480). Here, the correction torque Tvc is a torque that is adjusted so that the voltage VH of the high voltage system power line 54a, that is, the voltage of the capacitor 57 is equal to or lower than the withstand voltage thereof. Can be obtained by multiplying the difference by a proportional gain.

  Tm1 * = -ρ ・ Te * / (1 + ρ) (4)

  When the target rotational speed Ne * and target torque Te * of the engine 22 and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set in this manner, the target rotational speed Ne * and the target torque Te * are transmitted to the engine ECU 24 with the torque command Tm1. * And Tm2 * are transmitted to the motor ECU 40 (step S490), and the drive control routine for specifying the insulation resistance lowering portion is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * performs fuel injection control, ignition control, and intake air amount control so that the engine 22 is operated at an operating point based on the target rotational speed Ne * and the target torque Te *. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 *, for example, controls the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. Perform switching control. By such control, the required torque Tr * is output to the drive shaft 32 and is basically accompanied by conversion of power from the engine 22 into electric power and conversion into power again without charging and discharging the battery 50. In response to the change in the required torque Tr *, the torque corresponding to the required torque Tr * can be output to the drive shaft 32 with the charge and discharge of the capacitor 57 within the capacity range of the capacitor 57 to travel. FIG. 10 shows an example of a collinear diagram showing the dynamic relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when traveling in the battery-less traveling mode.

  Note that the control of the step-up converter 55 during the execution of the drive control routine for specifying the insulation resistance lowering portion is performed by the hybrid electronic control unit 70 unless otherwise controlled by the processing for specifying the insulation resistance lowering portion described later. The target voltage VHtag of the high voltage system power line 54a is set based on the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 and the rotational speeds Nm1 and Nm2, and the voltage of the high voltage system power line 54a from the voltage sensor 57a is set. Switching control of the transistors T31 and T32 of the boost converter 55 is performed so that VH becomes the target voltage VHtag. Here, in the embodiment, the target voltage VHtag of the high voltage system power line 54a is a voltage that can drive the motor MG1 at the target operating point (torque command Tm1 *, rotation speed Nm1) of the motor MG1 and the target operating point of the motor MG2 ( The larger one of the voltages that can drive the motor MG2 with the torque command Tm2 * and the rotation speed Nm2) is set within the range of the maximum allowable voltage VHmax, and when only one of the motors is driven, The voltage that can be driven at the target operating point of the motor is set within the range of the maximum allowable voltage VHmax. In the embodiment, the maximum allowable voltage VHmax of the high voltage system power line 54a is the maximum voltage of the high voltage system power line 54a that may be boosted by the boost converter 55, and is a value slightly lower than the breakdown voltage of the capacitor 57 and the breakdown voltage thereof. A predetermined one can be used. The drive control for specifying the insulation resistance lowering portion has been described above. Next, a process for detecting a decrease in insulation resistance will be described. This insulation resistance reduction detection process is executed when the system is started by ignition-on. Therefore, the insulation determination executed in this detection process is performed in the normal driving mode (engine operation mode, motor operation mode). Performed while driving.

  When the insulation resistance lowering detection processing routine of FIG. 3 is executed, the CPU 72 of the hybrid electronic control unit 70 first uses the voltage waveform from the voltage waveform output circuit 90 to present the current viewed from the connection point Cn in the electrical system. Insulation is determined for the current connection site, which is the connection site (step S100). Here, in the present embodiment, the insulation determination of the current connection portion is performed by comparing the amplitude of the voltage waveform from the voltage waveform output circuit 90 with the determination threshold value.

  When the insulation resistance is normal as a result of the insulation determination (step S110), the process returns to step S100. When the insulation resistance is abnormal as the result of the insulation determination (step S110), the warning lamp 89 is turned on (step S120). ), A value 1 is set to the abnormality detection flag F stored in the flash memory 78 and set to 0 as an initial value (step S130), and the insulation resistance decrease detection processing routine is terminated. Heretofore, the detection process for the decrease in insulation resistance has been described. Next, the process for identifying the insulation resistance lowering portion will be described.

  4 is executed, the CPU 72 of the hybrid electronic control unit 70 first inputs the abnormality detection flag F stored in the flash memory 78 (step S200), and inputs the abnormality. Processing for determining whether or not the detection flag F is a value 1 is executed (step S210). When the abnormality detection flag F is 0, it is determined that a decrease in insulation resistance has not been detected, and the insulation resistance decrease portion specifying process routine is terminated as it is. In this case, the traveling in the normal traveling mode is continued.

  When the abnormality detection flag F is a value of 1, it is determined that a decrease in insulation resistance has been detected, and the operation of the inverter 62 for driving the air conditioning compressor 61 is switched between the gate cutoff and the voltage waveform output circuit 90 Based on the voltage waveform, it is determined whether or not the insulation resistance is lowered in the air conditioner area on the air conditioning compressor 61 side from the inverter 62 (step S220). Specifically, in this determination, if the insulation determination is made based on the voltage waveform from the voltage waveform output circuit 90 when the inverter 62 is operated and the air conditioning compressor 61 is energized, the insulation resistance is determined to be abnormal, and the inverter When insulation is determined based on the voltage waveform from the voltage waveform output circuit 90 when the air conditioning compressor 61 is not energized with the gate 62 shut off, the insulation resistance is reduced in the air conditioner area when it is determined that the insulation resistance is normal. It was decided that it occurred.

  Subsequently, switching control of the step-up converter 55 is performed so that the voltage VH of the high voltage system power line 54a becomes the maximum allowable voltage VHmax (step S230), and for the evacuation traveling so that the traveling in the direct traveling mode is started. A direct running mode is set out of the modes (step S240). The reason why the voltage VH of the high voltage system power line 54a is boosted to the maximum allowable voltage VHmax will be described later. When the straight traveling mode is set, the traveling in the direct traveling mode is started by the drive control routine for specifying the insulation resistance lowering portion in FIG.

  When traveling in the straight traveling mode is started in this manner, the operation of the inverter 42 for driving the motor MG2 and the switching of the gate are switched, and the motor MG2 side from the inverter 42 is based on the voltage waveform from the voltage waveform output circuit 90. It is determined whether or not the insulation resistance is reduced in the second motor area (step S250). In this determination, specifically, a voltage waveform output when the motor MG2 is energized by switching the inverter 42 temporarily so that no torque is output from the motor MG2 (so that the d-axis current flows through the motor MG2). If insulation is determined based on the voltage waveform from circuit 90, the insulation resistance is determined to be abnormal, and insulation is determined based on the voltage waveform from voltage waveform output circuit 90 when inverter 42 is gated and motor MG2 is not energized. When it is determined that the insulation resistance is normal, it is determined that the insulation resistance has decreased in the second motor area. Here, during traveling in the straight traveling mode, since the inverter 42 is gate-cut off, the voltage waveform from the voltage waveform output circuit 90 when the motor MG2 is not energized can be input. Therefore, the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 when the motor MG2 is not energized may be performed before the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 when the motor MG2 is energized. Alternatively, it may be performed after the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 when the motor MG2 is energized. As described above, it is possible to determine whether or not the insulation resistance is reduced in the second motor area by using the traveling state in the direct traveling mode.

  Subsequently, the electric travel mode is set in the retreat travel mode so that travel in the electric travel mode is started (step S260). When the electric travel mode is set, the travel in the electric travel mode is started by the drive control routine for specifying the insulation resistance lowering portion in FIG.

  When running in the electric running mode is started in this way, the operation of the inverter 41 for driving the motor MG1 and the switching of the gate are switched, and the motor MG1 side is driven from the inverter 41 based on the voltage waveform from the voltage waveform output circuit 90. It is determined whether or not the insulation resistance is reduced in the first motor area (step S270). In this determination, specifically, the voltage waveform when the motor MG1 is energized by temporarily switching the inverter 41 so that no torque is output from the motor MG1 (so that the d-axis current flows through the motor MG1). When insulation is determined based on the voltage waveform from the output circuit 90, it is determined that the insulation resistance is abnormal, and insulation is performed based on the voltage waveform from the voltage waveform output circuit 90 when the inverter MG is shut off and the motor MG1 is not energized. When the determination is made, when it is determined that the insulation resistance is normal, it is determined that the insulation resistance has decreased in the first motor area. Here, while traveling in the electric travel mode, since the inverter 41 is gate-cut off, the voltage waveform from the voltage waveform output circuit 90 when the motor MG1 is not energized can be input. Therefore, the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 when the motor MG1 is not energized may be performed before the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 when the motor MG1 is energized. Alternatively, it may be performed after the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 when the motor MG2 is energized. As described above, it is possible to determine whether or not the insulation resistance is reduced in the first motor area by using the traveling state in the electric traveling mode.

  Here, the reason why the voltage VH of the high voltage system power line 54a is boosted to the maximum allowable voltage VHmax will be described. When traveling in the straight traveling mode, the motor MG2 generates a counter electromotive voltage according to the rotational speed Nm2, and when traveling in the electric traveling mode, the motor MG1 generates a counter electromotive voltage according to the rotational speed Nm1. Further, when the back electromotive voltage of the motor MG2 or the back electromotive voltage of the motor MG1 becomes larger than the voltage VH of the high voltage system power line 54a, the voltage waveform from the voltage waveform output circuit 90 is affected, and the determination threshold is determined to be insulation. For example, the insulation determination cannot be normally performed based on the voltage waveform from the voltage waveform output circuit 90. Therefore, in the embodiment, the voltage VH of the high voltage system power line 54a is boosted to the maximum allowable voltage VHmax, so that the counter electromotive voltage of the motor MG2 and the motor MG1 The counter electromotive voltage is prevented from becoming higher than the voltage VH of the high voltage system power line 54a. Thereby, the insulation determination based on the voltage waveform from the voltage waveform output circuit 90 can be more appropriately performed using the traveling state in the straight traveling mode and the traveling state in the electric traveling mode.

  Next, the battery-less travel mode is set in the retreat travel mode so that the boost converter 55 is stopped and the travel in the battery-less travel mode is started (step S480). When the battery-less travel mode is set, travel in the battery-less travel mode is started by the drive control routine for specifying the insulation resistance lowering portion in FIG.

  When traveling in the battery-less traveling mode is started in this way, the system main relay 56 is turned from on to off, and the insulation resistance decreases in the battery area on the battery 50 side from the system main relay 56 based on the voltage waveform from the voltage waveform output circuit 90. It is determined whether or not it has occurred (step S290). Specifically, in this determination, the insulation resistance is determined when the insulation determination is performed based on the voltage waveform from the voltage waveform output circuit 90 when the system main relay 56 is turned on after the start of traveling in the batteryless traveling mode. If the insulation resistance is determined to be abnormal again when the insulation determination is made based on the voltage waveform from the voltage waveform output circuit 90 with the system main relay 56 turned off after the determination, the battery area It was determined that there was a decrease in insulation resistance. As described above, it is possible to determine whether or not the insulation resistance is reduced in the battery area by using the traveling state in the battery-less traveling mode. In the embodiment, the system main relay 56 is turned on immediately after the start of running in the battery-less running mode, but the system main relay 56 is turned off after the battery area is determined in step S490.

  In this way, the system main relay 56 is turned off and the batteryless travel mode is set to wait for the ignition switch 80 to turn off the ignition (step S300). When the ignition is turned off, the air conditioner area, the first motor area, the second Based on the determination result of each of the motor area and the battery area, a part of the electric system where the insulation resistance is reduced is identified (step S310), and a process for stopping the vehicle is executed (step S320). ), The insulation resistance lowering part specifying process routine is terminated. In the embodiment, the part where the insulation resistance is reduced is determined in the embodiment, when it is determined that the insulation resistance is reduced in one of the areas. It is assumed that it is performed by specifying that the portion is generated, and information indicating the specified area is stored in the flash memory 78. In addition, when it is not determined that a decrease in insulation resistance occurs in any of the areas, or when it is determined that a decrease in insulation resistance occurs in two or more areas of each area, In the embodiment, the part where the insulation resistance is reduced when the ignition is turned on next time and this routine is executed is specified. In the embodiment, after the value 1 is set in the abnormality detection flag F, the travel in the battery-less travel mode is performed after the travel in the direct travel mode and the travel in the electric travel mode, and the ignition is turned off. Since waiting, the system main relay 56 is turned off again after the system main relay 56 is turned off to determine whether or not the battery area is a portion where the insulation resistance is lowered during traveling in the batteryless traveling mode. Can be turned off. Thereby, it is possible to suppress the occurrence of inconvenience such as a large current flowing through the system main relay 56 by turning the system main relay 56 from OFF to ON again.

  According to the hybrid vehicle 20 of the embodiment described above, one of a plurality of parts including the motors MG1, MG2, the air conditioning compressor 61, and the battery 50 according to the states of the inverters 41, 42, the inverter 62, and the system main relay 56. After a decrease in the insulation resistance of the electrical system (current connection site) is detected based on the voltage waveform corresponding to the insulation resistance of the electrical system (current connection site) consisting of parts or all, the decrease in insulation resistance among the plurality of sites When the system main relay 56 is turned on and the inverter 42 is shut off, the engine 22 is operated and the motor MG1 is driven to specify the input / output limits Win and Wout of the battery 50. In the direct running mode in which the vehicle travels with the required torque Tr * required for traveling, and the system main relay 56 The motor 22 is driven and the motor MG2 is driven in a state where the gate of the inverter 41 is shut off and the motor 50 is driven with the required torque Tr * within the range of the input / output limits Win and Wout of the battery 50. Driving in the battery-less driving mode in which the engine 22 is operated and the motor MG1 and the motor MG2 are driven to drive the battery 50 within the range of the withstand voltage of the capacitor 57 without charging / discharging the battery 50. The engine 22, the inverter 41, the inverter 42, and the system main relay 56 are controlled so that traveling is performed, respectively, and traveling in the direct traveling mode, traveling in the electric traveling mode, and traveling in the batteryless traveling mode, respectively. Based on the voltage waveform from the voltage waveform output circuit 90 when being performed, Since identifies the site where reduction of Chi insulation resistance occurs, it is possible to perform processing for identifying the site where reduction in insulation resistance occurred during travel. As a result, in order to identify the portion where the decrease in the insulation resistance occurs more quickly after the decrease in the insulation resistance of the electric system is detected based on the voltage waveform from the voltage waveform output circuit 90 during the traveling in the normal traveling mode. Can be processed. Therefore, as compared with the case where the process of specifying the insulation resistance lowering portion is performed when the ignition is turned off, the voltage waveform output circuit 90 from the traveling until the specification of the insulation resistance lowering portion is performed after the detection of the insulation resistance reduction. Can be prevented from temporarily returning to normal, and the portion where the insulation resistance is reduced can be more reliably identified.

  In the hybrid vehicle 20 of the embodiment, after the value 1 is set in the abnormality detection flag F, the traveling in the straight traveling mode, the traveling in the electric traveling mode, and the traveling in the batteryless traveling mode are performed in this order, and each traveling mode. The region where the insulation resistance has decreased is identified based on the voltage waveform from the voltage waveform output circuit 90 during traveling in the straight traveling mode after the value 1 is set in the abnormality detection flag F, The setting order of the electric travel mode and the battery-less travel mode may be any. For example, when traveling with the battery-less travel mode set to the first or second, the system main relay 56 is turned from off to on during travel in the battery-less travel mode, and then the direct travel mode or the electric travel mode is set. It is good also as what starts driving | running | working.

  In the hybrid vehicle 20 of the embodiment, after the value 1 is set in the abnormality detection flag F, the voltage waveform from the voltage waveform output circuit 90 during traveling in each traveling mode of the direct traveling mode, the electric traveling mode, and the batteryless traveling mode. Based on the above, it is determined whether each area such as the first motor area, the second motor area, and the battery area is a portion where the insulation resistance is reduced, and based on the determination result of each area when the ignition is turned off However, when all the determination results for each area are obtained, the insulation resistance is determined based on the determination results for each area at the timing before the ignition is turned off. It is good also as what specifies the part which a fall has arisen.

  In the hybrid vehicle 20 of the embodiment, after the value 1 is set in the abnormality detection flag F, the voltage waveform from the voltage waveform output circuit 90 during traveling in each of the straight traveling mode, the electric traveling mode, and the batteryless traveling mode is displayed. When it is determined whether each area such as the first motor area, the second motor area, the battery area, or the like is a part where the insulation resistance has decreased, and the ignition is turned off during traveling in the batteryless traveling mode. Based on the determination results of each area, the part where the insulation resistance has decreased is specified.However, after the battery area is determined during traveling in the battery-less traveling mode, the vehicle travels in the normal traveling mode. It is also possible to start and wait for the ignition off while traveling in the normal traveling mode.

  In the hybrid vehicle 20 of the embodiment, after the value 1 is set in the abnormality detection flag F, the voltage VH of the high voltage system power line 54a is boosted to the maximum allowable voltage VHmax to drive in the straight traveling mode and in the electric traveling mode. The voltage VH of the high voltage system power line 54a is the first counter electromotive voltage corresponding to the rotational speed Nm1 of the motor MG1 generated by the rotation of the motor MG1 in the electric travel mode. A predetermined voltage that is determined in advance as a voltage that is greater than the larger one of the electromotive voltage and the second counter electromotive voltage that is the counter electromotive voltage according to the rotation speed Nm2 of the motor MG2 generated by the rotation of the motor MG2 in the straight traveling mode. It is good also as what carries out driving | running | working in a direct drive mode, and driving | running | working in an electric drive mode. In the electric travel mode, the voltage VH of the high voltage system power line 54a is boosted to the first counter electromotive voltage or more, and in the direct travel mode, the voltage VH of the high voltage system power line 54a is boosted to the second counter electromotive voltage or more. It is good also as what to do.

  In the hybrid vehicle 20 of the embodiment, when traveling in the straight traveling mode is started after the abnormality detection flag F is set to the value 1 while traveling in the normal traveling mode (engine operation mode, motor operation mode), Switching of the operation of the inverter 42 for driving the motor MG2 and switching of the gate is performed, and the insulation resistance of the second motor area on the motor MG2 side from the inverter 42 is lowered based on the voltage waveform from the voltage waveform output circuit 90. The voltage waveform is obtained by switching from the normal traveling mode in which the inverter 42 is operated to the direct traveling mode in which the inverter 42 is gate-cut and starting traveling. When it is determined based on the voltage waveform from the output circuit 90 that the insulation resistance of the current connection portion has changed normally from an abnormality Or as a second motor area is determined to be a portion that occurs a decrease in insulation resistance. Similarly, the current connected portion is insulated based on the voltage waveform from the voltage waveform output circuit 90 by switching from the straight traveling mode in which the inverter 41 is operated to the electric traveling mode in which the inverter 41 is gate-cut and starting traveling. When it is determined that the resistance has changed from abnormal to normal, the first motor area may be determined to be a portion where a decrease in insulation resistance occurs.

  In the hybrid vehicle 20 of the embodiment, the voltage VH of the high voltage system power line 54a is adjusted within the range of the voltage VL of the battery voltage system power line 54b to the maximum allowable voltage VHmax, and the high voltage system power line 54a and the low voltage system power are adjusted. Although the boost converter 55 that exchanges power with the line 54b is provided, the boost converter 55 may not be provided.

  In the hybrid vehicle 20 of the embodiment, the power from the motor MG2 is output to the drive shaft 32 connected to the drive wheels 39a and 39b. However, as illustrated in the hybrid vehicle 120 of the modification of FIG. The power from MG2 may be output to an axle (an axle connected to wheels 39c and 39d in FIG. 11) different from an axle (an axle connected to drive wheels 39a and 39b) to which drive shaft 32 is connected. .

  In the hybrid vehicle 20 of the embodiment, the power from the engine 22 is output to the drive shaft 32 connected to the drive wheels 39a and 39b via the planetary gear 30 with the drive of the motor MG1, and the power from the motor MG2 is driven to the drive shaft. In addition to this configuration, an axle to which a drive shaft 32 to which power from the engine 22 and the motor MG2 is output is connected as illustrated in the hybrid vehicle 220 of the modified example of FIG. A motor MG3 that outputs power to an axle (an axle connected to the wheels 39c and 39d in FIG. 12) different from the (an axle connected to the drive wheels 39a and 39b) may be provided.

  In the hybrid vehicles 20 and 20B of the embodiment, the power from the engine 22 is output to the drive shaft 32 connected to the drive wheels 39a and 39b via the planetary gear 30 with the drive of the motor MG1, and the power from the motor MG2 is output. Although output to the drive shaft 32, the motor MG1 is attached to the first drive shaft connected to the drive wheels 39a and 39b via the transmission 330, as illustrated in the hybrid vehicle 320 of the modified example of FIG. Thus, the engine 22 is connected to the rotation shaft of the motor MG1 via the clutch 329, so that the power from the engine 22 is output to the first drive shaft via the rotation shaft of the motor MG1 and the transmission 330 and from the motor MG1. Power is output to the first drive shaft via the transmission 330 and connected to the drive wheels 39a and 39b in addition to this configuration. 1 the drive shaft second drive shaft that is different from the may output the power from the motor MG2 connecting the motor MG2 to (wheel in FIG. 13 39c, connected to the drive shaft 39d) to the second drive shaft.

  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 engine 22 corresponds to the “internal combustion engine”, the motor MG1 corresponds to the “first electric motor”, the inverter 41 corresponds to the “first inverter”, and the motor MG2 corresponds to the “second electric motor”. The inverter 42 corresponds to a “second inverter”, the battery 50 corresponds to a “secondary battery”, the system main relay 56 corresponds to a “relay”, and the voltage waveform output circuit 90 corresponds to “insulation resistance signal detection means”. The insulation resistance lowering detection processing routine of FIG. 3 for setting the value 1 to the abnormality detection flag F based on the voltage waveform from the voltage waveform output circuit 90 during traveling in the normal traveling mode after the system is started. When the value is set to 1 in the abnormality detection flag F, the voltage waveform output circuit 90 during traveling in the straight traveling mode, the electric traveling mode, and the batteryless traveling mode is used. The insulation resistance lowering part specifying process routine of FIG. 4 for specifying the part where the insulation resistance drop occurs among the plurality of parts including the second motor area, the first motor area, and the battery area based on the pressure waveform, The target rotational speed Ne * and target torque Te * of the engine 22 and the engine operation stop command, and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 so as to travel in the respective modes for retreat travel set in the routine of FIG. The hybrid electronic control unit 70 that executes the drive control routine for retreat travel of FIG. 5 that transmits the gate cutoff command of the inverters 41 and 42 to the engine ECU 24 and the motor ECU 40 and keeps the system main relay 56 on, and the target Engine E that controls the engine 22 in response to the rotational speed Ne *, the target torque Te *, and an engine operation stop command And U24, the torque command Tm1 *, Tm2 *, the motor ECU40 for controlling inverters 41 and 42 receive gate blocking instruction inverters 41 and 42 correspond to the "insulation resistance decrease part identification unit". Further, the boost converter 55 corresponds to a “boost converter”, and the planetary gear 30 corresponds to a “planetary gear mechanism”.

  Here, the “internal combustion engine” is not limited to the engine 22 as an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, but may be any engine that can output driving power. For example, any type of internal combustion engine such as a hydrogen engine may be used. The “first motor” is not limited to the motor MG1 as a synchronous generator motor, but may be another type of motor such as an induction motor as long as it can generate power using power from an internal combustion engine. It doesn't matter. The “first inverter” is not limited to the inverter 41 and may be any one as long as it drives the first electric motor. The “second motor” is not limited to the motor MG2 as a synchronous generator motor, and may be another type of motor such as an induction motor as long as it can output driving power. . The “second inverter” is not limited to the inverter 42 and may be any device as long as it drives the second electric motor. The “secondary battery” is not limited to the battery 50 configured as a lithium ion secondary battery, but includes a first inverter and a second inverter 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 is connected via a relay to a drive system to which is connected. The “relay” is not limited to the system main relay 56, and any relay can be used as long as it connects the secondary battery to the first motor and the second motor via the first inverter and the second inverter. I do not care. The “insulation resistance signal detection means” is not limited to the voltage waveform output circuit 90, and the first motor, the second motor, and the secondary battery according to the states of the first inverter, the second inverter, and the relay. Any signal may be used as long as it detects an insulation resistance signal corresponding to the insulation resistance of an electric system composed of a part or all of a plurality of parts including As the “insulation resistance lowering portion specifying means”, the insulation resistance lowering detection processing routine of FIG. 3 is executed, the insulation resistance lowering portion specifying processing routine of FIG. 45 is executed, or the retreat travel drive control routine of FIG. 5 is executed. The engine 22 and the motors MG1, MG2, the system main relay 56, etc. are not limited to the one that specifies the portion where the insulation resistance is reduced, and the electrical system based on the detected insulation resistance signal is not limited. When identifying a portion of the plurality of portions where the decrease in insulation resistance has been detected since the decrease in insulation resistance has been detected, the internal combustion engine is operated with the relay turned on and the second inverter is shut off, and the first The first electric motor traveling that travels by driving force based on the required driving force required for traveling by driving the electric motor, the relay is turned on, the operation of the internal combustion engine is stopped, and the first The secondary battery is driven by driving the second electric motor with the inverter cut off from the gate and driving by the driving force based on the required driving force, driving the internal combustion engine and driving the first electric motor and the second electric motor. The internal combustion engine, the first inverter, the second inverter, and the relay are controlled so that the non-charging / discharging traveling that travels by the driving force based on the required driving force without charging / discharging the motor, respectively, (2) A part in which a decrease in insulation resistance occurs among a plurality of parts based on an insulation resistance signal detected by the insulation resistance signal detection means when electric motor traveling and non-charge / discharge traveling are performed. It does not matter as long as there is any. Further, the “boost converter” is not limited to the boost converter 55, and may boost the power supplied via the relay from the battery system to which the secondary battery is connected and supply it to the drive system. It does not matter as long as it is anything. The “planetary gear mechanism” is not limited to the planetary gear 30, and three rotating elements are connected to three axes of the output shaft of the internal combustion engine, the rotating shaft of the first electric motor, and the driving shaft connected to the axle. Anything can 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 hybrid vehicles.

  20, 120, 220, 320 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 30 planetary gear, 32 drive shaft, 38 differential gear, 39a, 39b drive wheel, 39c, 39d wheel, 40 electronic control unit for motor (motor ECU), 41, 42 inverter, 50 battery, 52 electronic control unit for battery (battery ECU), 54a high voltage system power line, 54b battery voltage system power line, 55 boost converter, 56 system Main relay, 57, 58 capacitor, 57a, 57b Voltage sensor, 60 Air conditioning device, 61 Air conditioning compressor, 62 Inverter, 70 Hybrid electronic control unit, 72 CPU, 74 ROM, 76 RAM, 78 Flash memory, 80 Ignition switch, 82 Shift position sensor, 84 Accel pedal position sensor, 86 Brake pedal position sensor, 88 Vehicle speed sensor, 89 Warning light, 90 Voltage waveform output circuit, 92 Oscillator, 94 Detection resistance, 95 Capacitor , 96 low pass filter, 329 clutch, 330 transmission, D11 to D16, D21 to D26, D31, D32, D41 to D46 diode, L reactor, MG, MG1, MG2, MG3 motor, T11 to T16, T21 to T26, T31 , T32, T41 to T46 transistors.

Claims (5)

An internal combustion engine capable of outputting traveling power, a first electric motor capable of generating electric power using the power from the internal combustion engine, a first inverter driving the first electric motor, and a first inverter capable of outputting traveling power Two motors, a second inverter that drives the second motor, a secondary battery, and the secondary battery is connected to the first motor and the second motor via the first inverter and the second inverter. A hybrid vehicle comprising a relay,
Insulation of an electric system comprising a part or all of a plurality of parts including the first electric motor, the second electric motor, and the secondary battery according to the states of the first inverter, the second inverter, and the relay. Insulation resistance signal detecting means for detecting an insulation resistance signal according to the resistance;
The relay is turned on when the portion of the plurality of portions where the decrease in insulation resistance has occurred after the decrease in the insulation resistance of the electrical system is detected based on the detected insulation resistance signal. (2) driving the first internal motor with the inverter shut off and driving the first motor to drive with a driving force based on a required driving force required for driving; and turning on the relay. A second motor running that drives the second motor with a driving force based on the required driving force in a state where the operation of the internal combustion engine is stopped and the first inverter is shut off, and the internal combustion engine And driving the first motor and the second motor to drive the secondary battery without charging / discharging and running with a driving force based on the required driving force, respectively, When the internal combustion engine, the first inverter, the second inverter, and the relay are controlled so that the first electric motor traveling, the second electric motor traveling, and the non-charge / discharge traveling are performed, respectively. Insulation resistance lowering part specifying means for specifying a part of the plurality of parts where a decrease in insulation resistance occurs based on an insulation resistance signal detected by the insulation resistance signal detecting means;
A hybrid car with The hybrid vehicle according to claim 1,
The insulation resistance lowering portion specifying means shuts off the gate of the second inverter from the insulation resistance signal detected by the insulation resistance signal detecting means and the state of the first motor running when the first motor running is being performed. And the second electric motor from the second inverter based on the insulation resistance signal detected by the insulation resistance signal detection means when the second inverter is operated so that torque is not output from the second electric motor. determining whether decrease in insulation resistance at the site of side occurs, is the insulation resistance signal and the second electric motor cars detected by the insulation resistance signal detecting means when said second electric motor driving is being performed the absolute when torque from said first motor to release the gate of interruption of the first inverter from the condition actuates the first inverter so as not to be output Based on the insulation resistance signal detected by the resistance signal detection means, it is determined whether or not the insulation resistance is lowered at the first motor side portion from the first inverter, and the non-charge / discharge running is performed. Whether or not a decrease in insulation resistance occurs in the secondary battery side of the relay based on the insulation resistance signal detected by the insulation resistance signal detection means when the relay is turned off from on It is a means to determine
Hybrid car. A hybrid vehicle according to claim 1 or 2,
A boost converter that boosts power supplied from the battery voltage system to which the secondary battery is connected via the relay and supplies the boosted power to the drive voltage system to which the first inverter and the second inverter are connected;
The first electric motor and the second electric motor are electric motors that generate a counter electromotive voltage when rotated,
In the insulation resistance lowering portion specifying means, the voltage of the drive voltage system is influenced by the back electromotive voltage generated by the rotation of the first motor and the back electromotive voltage generated by the rotation of the second motor on the insulation resistance signal. The internal combustion engine, the first inverter, and the second inverter are performed so that the first electric motor traveling and the second electric motor traveling are performed in a state where the first electric motor traveling and the second electric motor traveling are performed in a state where the voltage is not less than a predetermined voltage determined as a voltage that can be suppressed And means for controlling the relay and the boost converter,
Hybrid car. A hybrid vehicle according to claim 3,
The predetermined voltage is a maximum value of the voltage of the drive voltage system that can be boosted by the boost converter.
Hybrid car. A hybrid vehicle according to any one of claims 1 to 4,
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 the first electric motor, and a driving shaft connected to an axle;
The second electric motor is connected to the drive shaft;
Hybrid car.

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