JP2019073204A - Hybrid vehicle - Google Patents

Abstract

To prevent driving force from being output from a second motor when a second motor control device is broken without complicating a communication circuit.SOLUTION: A hybrid vehicle includes: an engine; a first motor; a planetary gear to which the engine, the first motor and a driving shaft are connected; a second motor capable of inputting/outputting power to/from the driving shaft; a battery; a first inverter for driving the first motor; a second inverter for driving the second motor; an MG1 ECU for controlling the first inverter; an MG2 ECU for controlling the second inverter; and a relay (SMR) for relaying/intercepting a power line between the first and second inverters and the battery. The MG1 ECU and the MG2 ECU are configured to mutually monitor presence/absence of failure thereof. When the MG1 ECU detects occurrence of failure in the MG2 ECU, the relay is intercepted, and the first inverter is controlled by the MG1 ECU so as to prevent torque from being output from the first motor.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a hybrid vehicle.

  Conventionally, as a hybrid vehicle of this type, an engine, a first motor (first motor generator), a planetary gear mechanism in which the engine, the first motor, and an output shaft are connected to three rotating elements, an output shaft A second motor (second motor generator) connected, a battery, a first inverter for converting power between the first motor and the battery, and a second for converting power between the second motor and the battery A hybrid vehicle is proposed that includes an inverter, a first motor control device that controls the first inverter, and a second motor control device that controls the second inverter (see, for example, Patent Document 1). In this hybrid vehicle, the first motor control device and the second motor control device are configured to mutually monitor the presence or absence of a failure, and the second motor control device has a failure in the first motor control device. When it is detected, the second motor control device drives the second motor to perform retraction travel or immediately prohibits the travel of the vehicle.

Unexamined-Japanese-Patent No. 2017-136989

  In the above-described hybrid vehicle, when a failure occurs in the first motor control device, the traveling of the vehicle can be prohibited by shutting down the second inverter by the second motor control device. However, if a failure occurs in the second motor control device, the second motor control device can not shut down the second inverter. In this case, in order to stop the driving of the second motor, it is conceivable to provide a signal circuit that outputs a shutdown signal to the second inverter on the side of the first motor control device that controls the first inverter. Increases complexity and cost.

  The hybrid vehicle of the present invention is mainly intended to prevent the driving force from being output from the second motor when the second motor control device fails, without complicating the communication circuit.

  The hybrid vehicle of the present invention adopts the following means in order to achieve the above-mentioned main object.

The hybrid vehicle of the present invention is
A planetary gear mechanism in which an engine, a first motor, a drive shaft connected to an output shaft of the engine and a rotational shaft of the first motor and an axle to three rotating elements are connected, power is transmitted to the drive shaft A second motor capable of input / output, a power storage device, a first inverter for driving the first motor, a second inverter for driving the second motor, the power storage device, the first inverter and the second inverter And a relay for connecting and disconnecting a power line between
A first motor control device for controlling the first inverter;
A second motor control device for controlling the second inverter;
Have
When the second motor control device fails, the first motor control device controls the first inverter so that the torque is not output from the first motor while the relay is shut off.
Make it a gist.

  In the hybrid vehicle of the present invention, when the second motor control device fails, the first motor control device controls the first inverter so that the torque is not output from the first motor while the relay is shut off. As a result, the power storage device is disconnected from the second motor, and at the same time the supply of power from the first motor to the second motor is also cut off, so the second motor can not output torque. Therefore, it is not necessary to provide a signal circuit for shutting down the second inverter in the control device for the first motor, and without complicating the communication circuit, when the failure in the control device for the second motor causes the driving force from the second motor to It is possible not to output.

FIG. 1 is a block diagram schematically showing the configuration of a hybrid vehicle 20 as an embodiment of the present invention. FIG. 2 is a configuration diagram showing a configuration of an electric system including motors MG1 and MG2. 15 is a flowchart illustrating an example of an MG2ECU failure process executed by the HVECU 70; FIG. 10 is an explanatory view showing a state of interrupting the supply of power to the motor MG2 at the time of failure of the MG2 ECU.

  Next, modes for carrying out the present invention will be described using examples.

  FIG. 1 is a block diagram schematically showing the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown, the hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, a boost converter 56, and a hybrid electronic control unit (hereinafter referred to as And 70).

  The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil or the like as a fuel. The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing processing programs, a RAM for temporarily storing data, an input / output port, and a communication port, in addition to the CPU. . The engine ECU 24 receives signals from various sensors necessary for operation control of the engine 22, for example, a crank angle θcr from a crank position sensor 23 for detecting the rotational position of the crankshaft 26 of the engine 22 via an input port. It has been input. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through the output port. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotational speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23.

  The planetary gear 30 is configured as a single pinion type planetary gear mechanism. The rotor of the motor MG1 is connected to the sun gear of the planetary gear 30. The ring gear of the planetary gear 30 is connected with a drive shaft 36 connected to the drive wheel 38. The crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30 via a damper (not shown).

  The motor MG1 is configured, for example, as a synchronous generator motor, and as described above, the rotor is connected to the sun gear of the planetary gear 30. Inverter 41 is connected to battery 50 via boost converter 56. The motor MG1 is rotationally driven by the inverter 41 being controlled by a first motor electronic control unit (hereinafter referred to as "MG1 ECU") 40a.

  The motor MG2 is configured as, for example, a synchronous generator motor, and a rotor is connected to the drive shaft 36 via a reduction gear 37. Inverter 42 is connected to battery 50 via boost converter 56. The motor MG2 is rotationally driven by the inverter 42 being controlled by a second motor electronic control unit (hereinafter referred to as "MG2 ECU") 40b.

  The inverters 41 and 42 are connected to a power line (hereinafter referred to as a drive voltage system power line) 54 a. 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 in the reverse direction to the transistors T11 to T16 and T21 to T26. To D26. The transistors T11 to T16 and T21 to T26 are arranged in pairs of two so as to be on the source side and the sink side with respect to the positive electrode bus and the negative electrode bus of the drive voltage system power line 54a, respectively. The three-phase coils (U-phase, V-phase, W-phase) of the motors MG1 and MG2 are connected to respective connection points of Therefore, by adjusting the ratio of the on time of the paired transistors T11 to T16 and T21 to T26 in a state where a voltage is applied to the inverters 41 and 42, it is possible to form a rotating magnetic field in the three-phase coil. MG2 can be rotationally driven. A smoothing capacitor 57 is connected to the drive voltage system power line 54a. Since the inverters 41 and 42 share the positive electrode bus and the negative electrode bus of the drive voltage system power line 54a, the electric power generated by any of the motors MG1 and MG2 can be supplied to another motor.

  The inverter 41 monitors an abnormality such as short circuit, heating, or overcurrent of the transistors T11 to T16, and is configured to output a fail signal to the MG1 ECU 40a when any abnormality is detected. Similarly, the inverter 42 also monitors an abnormality such as short circuit, heating, or overcurrent of the transistors T21 to T26, and is configured to output a fail signal to the MG2 ECU 40b when any abnormality is detected.

  Boost converter 56 is connected to a power line (referred to as a battery voltage system power line) 54 b connected to drive voltage system power line 54 a and to battery 50 via system main relay 55. As shown in FIG. 2, this boost converter 56 is configured by two transistors T51 and T52, two diodes D51 and D52 connected in parallel in the reverse direction to the transistors T51 and T52, and a reactor L. . The two transistors T51 and T52 are connected to the positive electrode bus of the drive voltage system power line 54a, the negative electrode bus of the drive voltage system power line 54a and the negative electrode bus of the battery voltage system power line 54b, respectively, and the connection point of the transistors T51 and T52 and the battery Reactor L is connected to the positive electrode bus of voltage system power line 54b. Therefore, by turning on and off the transistors T51 and T52, the power of the battery voltage system power line 54b is boosted and supplied to the drive voltage system power line 54a, or the power of the drive voltage system power line 54a is stepped down to obtain the battery voltage system. It can be supplied to the power line 54b. A smoothing capacitor 58 is connected to the side of the boost converter 56 of the battery voltage system power line 54b.

  The boost converter 56 monitors an abnormality such as a short circuit, heating, or an overcurrent of the transistors T51 and T52, and is configured to output a fail signal to the MG1 ECU 40a when any abnormality is detected.

  Although not shown, the MG1 ECU 40a is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM for storing processing programs, a RAM for temporarily storing data, an input / output port, and a communication port. The MG1 ECU 40a receives signals from various sensors necessary to drive and control the motor MG1, for example, the rotational position θm1 from the rotational position detection sensor 43 for detecting the rotational position of the rotor of the motor MG1 and a current sensor not shown. Phase currents Iu1 and Iv1 applied from the inverter 41 to the motor MG1 are input through the input port. Also, drive voltage system voltage VH from a voltage sensor (not shown) attached to drive voltage system power line 54a and battery voltage system voltage VL from a voltage sensor (not shown) attached to battery voltage system power line 54b are input ports. It is input through. The MG1 ECU 40a outputs a switching control signal to the transistors T11 to T16 of the inverter 41, a switching control signal to the transistors T51 and T52 of the step-up converter 56, and the like via the output port. The MG1 ECU 40a is connected to the HVECU 70 via a communication port. The MG1 ECU 40a calculates the rotational speed Nm1 of the motor MG1 based on the rotational position θm1 of the rotor of the motor MG1 from the rotational position detection sensor 43.

  Although not shown, the MG2 ECU 40b is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM for storing processing programs, a RAM for temporarily storing data, an input / output port, and a communication port. Signals from various sensors necessary to drive and control the motor MG2, for example, the rotational position θm2 from the rotational position detection sensor 44 for detecting the rotational position of the rotor of the motor MG2, and a current sensor not shown Phase currents Iu2 and Iv2 applied from the inverter 42 to the motor MG1 are input through the input port. Further, a drive voltage system voltage VH from a voltage sensor (not shown) attached to the drive voltage system power line 54a is also input through the input port. A switching control signal or the like to the transistors T21 to T26 of the inverter 42 is output from the MG2 ECU 40b via the output port. The MG2 ECU 40 b is connected to the HVECU 70 via a communication port. The MG2 ECU 40b calculates the rotational speed Nm2 of the motor MG2 based on the rotational position θm2 of the rotor of the motor MG2 from the rotational position detection sensor 44.

  When the MG1 ECU 40a receives a fail signal from the inverter 41, the MG1 ECU 40a outputs a shutdown signal to the inverter 41 as necessary to shut down the transistors T11 to T16. When MG1 ECU 40a receives a fail signal from boost converter 56, it outputs a shutdown signal to boost converter 56 as required to shut down transistors T51 and T52. On the other hand, when the MG2 ECU 40b receives a fail signal from the inverter 42, it outputs a shutdown signal to the inverter 42 as necessary to shut down the transistors T21 to T26. The MG1 ECU 40a and the MG2 ECU 40b are communicably connected to each other, and monitor the presence or absence of a failure with each other by a watchdog timer or the like. When the MG1 ECU 40a detects that a failure has occurred in the MG2 ECU 40b, it transmits a fail signal indicating that to the HVECU 70. When the MG2 ECU 40 b detects that a failure has occurred in the MG 1 ECU 40 a, it transmits a fail signal indicating that fact to the HVECU 70.

  In the embodiment, the MG1 ECU 40a, the MG2 ECU 40b, the inverters 41 and 42, and the boost converter 56 are housed in a single case, and these are referred to as a power control unit (hereinafter referred to as "PCU") 40.

  The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery. As described above, the battery 50 is connected to the inverters 41 and 42 via the boost converter 56. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as "battery ECU") 52.

  Although not shown, the battery ECU 52 is configured as a microprocessor with a central CPU, and includes a ROM for storing processing programs, a RAM for temporarily storing data, an input / output port, and a communication port, in addition to the CPU. . The battery ECU 52 is attached to signals from various sensors necessary for managing the battery 50, for example, a battery voltage Vb from a voltage sensor (not shown) installed between the terminals of the battery 50 and an output terminal of the battery 50. A battery current Ib and the like from a current sensor (not shown) are input through the input port. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the storage ratio SOC based on the integrated value of the battery current Ib from a current sensor (not shown). The storage ratio SOC is a ratio of the capacity of power that can be discharged from the battery 50 to the total capacity of the battery 50.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing processing programs, a RAM for temporarily storing data, an input / output port, and a communication port, in addition to the CPU. Signals from various sensors are input to the HVECU 70 through input ports. Examples of signals input to the HVECU 70 include an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82, an accelerator opening Acc from the accelerator pedal position sensor 84, and a brake from the brake pedal position sensor 86. The pedal position BP, the vehicle speed V from the vehicle speed sensor 88, and the like can be mentioned. Various control signals are output from the HVECU 70 via the output port. As described above, the HVECU 70 is connected to the engine ECU 24, the MG1 ECU 40a, the MG2 ECU 40b, and the battery ECU 52 via the communication port.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, in particular, the operation when the MG2 ECU 40b breaks down, will be described. FIG. 3 is a flowchart showing an example of the MG2ECU failure process executed by the HVECU 70. This process is repeatedly performed every predetermined time (for example, every several msec).

  When the MG2ECU failure process is executed, the CPU of the HVECU 70 determines whether a fail signal indicating that the MG2ECU 40b has failed is received from the MG1 ECU 40a (S100). If it is determined that the fail signal is not received, the command value of engine 22 and motors MG1 and MG2 is set to corresponding engine ECU 24 or the like so as to output the required torque requested by the driver to drive shaft 36 if there is no other abnormality. The normal control to be transmitted to the MG1 ECU 40a and the MG2 ECU 40b is performed (S110), and the MG2 ECU failure processing ends. On the other hand, when it is determined that the fail signal has been received from MG1 ECU 40a, system main relay 55 is shut off (S120), and torque command Tm1 * of motor MG1 is set to the value 0 (S130). (S140), and the MG2 ECU failure processing ends. The MG1 ECU 40a that receives the torque command Tm1 * performs switching control of the transistors T11 to T16 of the inverter 41 so that the torque of the motor MG1 becomes 0. MG1 ECU 40a performs three-phase on control by turning on all the upper arms (transistors T11 to T13) of transistors T11 to T16 of inverter 41 or turning on all the lower arms (transistors T14 to T16). The torque of the motor MG1 may be zero.

  FIG. 4 is an explanatory view showing a state of interrupting the power supplied to the motor MG2 at the time of failure of the MG2 ECU. As shown, the inverter 42 for driving the motor MG2 is connected to the battery 50 through the system main relay (SMR) 55, so the battery 50 supplies the motor MG2 by shutting off the system main relay 55. Power can be cut off. On the other hand, since inverter 42 is also connected to inverter 41 driving motor MG1 via drive voltage system power line 54a, the electric power generated by motor MG1 is supplied to motor MG2, but is output from motor MG1. By setting the torque to the value 0, the power supplied from the motor MG1 to the motor MG2 can also be cut off. By cutting off the power supplied to the motor MG2 in this manner, it is possible to prevent the torque from being output from the motor MG2 even if the MG2 ECU 40b can not shut down the inverter 42 due to the failure of the MG2 ECU 40b.

  In the hybrid vehicle 20 of the embodiment described above, when the MG1 ECU 40a detects a failure of the MG2 ECU 40b, the system main relay 55 is shut off and the inverter 41 is controlled so that the torque output from the motor MG1 becomes a value 0. . Thus, the electric power supplied to the motor MG2 can be cut off, and the torque output from the motor MG2 can be set to the value 0. As a result, since it is not necessary to provide a signal circuit for shutting down the second inverter to the MG1 ECU 40a, torque can not be output from the motor MG2 at the time of failure of the MG2 ECU 40b without complicating the communication circuit. Can be safely stopped.

  In the hybrid vehicle 20 of the embodiment, the HVECU 70 and the MG1 ECU 40a are communicably connected to each other, and the HVECU 70 and the MG2 ECU 40b are communicably connected to each other. However, the HVECU 70 and the MG2 ECU 40b may not be directly communicably connected, and may be configured to be communicable via the MG1 ECU 40a. Even with such a configuration, when the MG1 ECU 40a detects a failure of the MG2 ECU 40b, it can transmit a fail signal to the HVECU 70, and the HVECU 70 can receive the fail signal and execute the MG2ECU failure processing.

  In the hybrid vehicle 20 of the embodiment, when the HVECU 70 receives a fail signal indicating a failure of the MG2 ECU 40 b from the MG1 ECU 40 a, the system main relay 55 is shut off and the torque command Tm 1 * of value 0 is output so that the torque is not output from the motor MG1. It was set as the structure transmitted to MG1ECU40a. However, for example, in a configuration in which system main relay 55 is shut off due to a failure of HVECU 70, etc., MG1ECU 40a is output from motor MG1 when MG1ECU 40a detects a failure of MG2ECU 40b in a state that system main relay 55 is shut off. The inverter 41 may be controlled so that the torque has a value of zero. In the hybrid vehicle of this modification, when the system main relay 55 is shut off due to a failure of the HVECU 70 or the like, first, evacuation traveling by batteryless traveling is performed. In batteryless traveling, the engine 22 and the motor MG1 (inverter 41) are controlled so that the motor MG1 generates electric power by the power output from the engine 22 while outputting required power required for traveling from the engine 22 and the motor MG1 This is performed by controlling the motor MG2 (inverter 42) so that all the generated electric power is consumed by the motor MG2. Then, when the MG1 ECU 40a detects a failure of the MG2 ECU 40b during battery-less travel, the MG1 ECU 40a controls the inverter 41 to set the torque output from the motor MG1 to a value 0. Thus, the vehicle can be safely stopped by preventing the torque from being output from the motor MG2. In this modification, the MG1ECU 40a does not transmit a fail signal to the HVECU 70. Therefore, the HVECU 70 and the MG1ECU 40a are not directly communicably connected, but are communicable via the MG2ECU 40b, that is, due to a failure of the MG2ECU 40b. Even when the HVECU 70 and the MG1ECU 40a can not communicate with each other, the MG1ECU 40a can be applied by confirming that the system main relay 55 is shut off.

  In the hybrid vehicle 20 of the embodiment, the battery 50 is used as the power storage device, but any device capable of storing power, such as a capacitor, may be used.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the section of "Means for Solving the Problems" will be described. In the embodiment, the engine 22 corresponds to the "engine", the motor MG1 corresponds to the "first motor", the planetary gear 30 corresponds to the "planet gear mechanism", and the motor MG2 corresponds to the "second motor". Battery 50 corresponds to a "power storage device", inverter 41 corresponds to a "first inverter", inverter 42 corresponds to a "second inverter", system main relay 55 corresponds to a "relay", and MG1 ECU 40a The MG2 ECU 40 b corresponds to a “first motor control device”.

  In addition, the correspondence of the main elements of the embodiment and the main elements of the invention described in the section of the means for solving the problem implements the invention described in the column of the means for solving the problem in the example. The present invention is not limited to the elements of the invention described in the section of “Means for Solving the Problems”, as it is an example for specifically explaining the mode for carrying out the invention. That is, the interpretation of the invention described in the section of the means for solving the problem should be made based on the description of the section, and the embodiment is an embodiment of the invention described in the section of the means for solving the problem. 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 by these Examples, In the range which does not deviate from the summary of this invention, it becomes various forms Of course it can be implemented.

  The present invention is applicable to the manufacturing industry of hybrid vehicles and the like.

  20 hybrid vehicles, 22 engines, 23 crank position sensors, 24 electronic control units for engines (engine ECUs), 26 crankshafts, 30 planetary gears, 36 drive shafts, 37 reduction gears, 38 drive wheels, 40 power control units (PCUs), 40a first motor electronic control unit (MG1ECU), 40b second motor electronic control unit (MG2ECU), 41, 42 inverters, 43, 44 rotational position detection sensors, 50 batteries, 52 battery electronic control units (battery ECU) , 54a drive voltage system power line, 54b battery voltage system power line, 55 system main relay (SMR), 56 boost converter, 57, 58 capacitor, 70 electronic control unit for hybrid HVECU), 80 ignition switch, 82 shift position sensor, 84 accelerator pedal position sensor, 86 brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor, T11 to T16, T21 to T26, T51, T52 transistor, D11 to D16, D21 to D26, D51, D52 Diodes, L reactor.

Claims (1)

A planetary gear mechanism in which an engine, a first motor, a drive shaft connected to an output shaft of the engine and a rotational shaft of the first motor and an axle to three rotating elements are connected, power is transmitted to the drive shaft A second motor capable of input / output, a power storage device, a first inverter for driving the first motor, a second inverter for driving the second motor, the power storage device, the first inverter and the second inverter And a relay for connecting and disconnecting a power line between
A first motor control device for controlling the first inverter;
A second motor control device for controlling the second inverter;
Have
When the second motor control device fails, the first motor control device controls the first inverter so that the torque is not output from the first motor while the relay is shut off.
Hybrid car.

Images