JP6606453B2 - Hybrid vehicle control system and motor control unit - Google Patents

Description

  The present invention relates to a hybrid vehicle control system and a motor control unit.

  In recent years, a hybrid vehicle (HEV) including an engine and a drive motor is known as a driving force source for driving the driving wheels of the vehicle. The hybrid vehicle also includes a high voltage battery that supplies power to the drive motor and a low voltage battery that supplies power to various auxiliary machines in the vehicle as a power supply source. Electric power is supplied to the low voltage battery from the high voltage battery via the DC / DC converter. Here, when some devices in the vehicle fail, the high-voltage battery may not be properly charged, and thus the electric power stored in each battery may be depleted early. In view of this, a technique relating to charging in the event of failure of some devices in the vehicle has been proposed.

  For example, in Patent Document 1, even if a failure occurs in a high-voltage battery and the battery is disconnected from the motor-driven regeneration circuit and the battery charging circuit, and the fluctuation of the regeneration voltage of the motor-driven regeneration circuit increases, There has been disclosed a technique for realizing stable charging of a low-voltage battery for auxiliary equipment without causing the operation to stop.

Japanese Patent No. 5171578

  By the way, the hybrid vehicle can be equipped with a hybrid control unit that integrally controls a plurality of control units. Further, as the drive motor, a motor generator having a function as a drive motor that is driven using electric power to generate a driving force of a vehicle and a generator that is driven using the driving force and generates electric power can be used. . The electric power generated by the motor generator is charged to the high voltage battery. For example, the hybrid control unit integrally controls the output of the driving force by the engine and the output of the driving force by the motor generator and power generation. When such a hybrid control unit fails, the high voltage battery is not properly charged. Therefore, since the electric power stored in each battery is depleted at an early stage, the vehicle falls into an early run impossible.

  Here, in order to prevent the electric power stored in each battery from being exhausted early, it is conceivable that when the hybrid control unit fails, the drive wheels and the motor generator are driven by the output of the engine. Thus, the vehicle can be run and the high-voltage battery can be continuously charged until the engine fuel is used up. In the case where the vehicle is driven by the output of the engine in this way when the hybrid control unit breaks down, it is considered desirable to increase the travelable distance.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a hybrid vehicle capable of further increasing the travelable distance when the hybrid control unit fails. It is to provide a control system and a motor control unit.

  In order to solve the above-described problems, according to an aspect of the present invention, an engine control unit that controls an engine that can output a driving force for driving a driving wheel, and a first power generator that can generate electric power using the output of the engine. A motor control unit that controls a second motor generator capable of generating electric power using the output of the first motor generator and the engine, and capable of generating electric power using the kinetic energy of the drive wheels during deceleration of the hybrid vehicle; and the engine A control unit and a hybrid control unit that outputs a control command to the motor control unit, wherein the engine control unit causes the engine to output a driving force when the hybrid control unit fails, thereby driving the driving wheel. The motor control unit is connected to the hybrid control unit. Provided is a control system for a hybrid vehicle that increases the ratio of the amount of power generated by the second motor generator to the amount of power generated by the first motor generator and the second motor generator as the vehicle speed increases when a failure occurs. Is done.

  When the accelerator is turned off when the hybrid control unit fails, the transmission of power between the drive wheel and the second motor generator and the engine is cut off, and the second motor generator using the kinetic energy of the drive wheel It may further include a transmission control unit that makes power generation possible by.

  Based on the vehicle speed, the engine control unit uses a driving force used for power generation by the first motor generator among driving forces output by the engine when the accelerator is off when the hybrid control unit fails. You may control.

  If the vehicle speed is higher than a threshold value when the accelerator is off when the hybrid control unit fails, the motor control unit stops power generation by the first motor generator, and the engine control unit You may stop the output by the said engine of the driving force used for the electric power generation by a motor generator.

  In order to solve the above problem, according to another aspect of the present invention, a first motor generator capable of generating electric power using an output of an engine capable of outputting a driving force for driving a driving wheel, and A motor control unit for controlling a second motor generator capable of generating electric power using the output of the engine and generating electric power using kinetic energy of the driving wheel during deceleration of the hybrid vehicle, wherein the driving wheel includes the engine The engine control unit that controls the engine and the hybrid control unit that outputs a control command to the motor control unit are driven by the output of the engine when the failure occurs, and the motor control unit is driven when the hybrid control unit fails As the vehicle speed increases, the first motor generator and the second motor generator Increasing the percentage of the power generation amount by the second motor-generator for power generation amount by the motor, the motor control unit, it is provided.

  As described above, according to the present invention, when the hybrid control unit fails, it is possible to further increase the travelable distance.

It is a mimetic diagram showing an example of schematic structure of a drive system of a hybrid vehicle concerning an embodiment of the present invention. It is a flowchart which shows an example of the flow of the process which engine ECU which concerns on the same embodiment performs. It is explanatory drawing which shows an example of transition of various state quantities in case control by the control system which concerns on the embodiment is performed when a hybrid ECU fails. It is explanatory drawing for demonstrating the operation state of a drive system when a hybrid ECU fails. It is explanatory drawing for demonstrating the operation state of a drive system when a hybrid ECU fails. It is explanatory drawing for demonstrating the operation state of a drive system when a hybrid ECU fails. It is explanatory drawing for demonstrating the operation state of a drive system when a hybrid ECU fails. It is explanatory drawing for demonstrating the operation state of a drive system when a hybrid ECU fails. It is explanatory drawing for demonstrating the operation state of a drive system when a hybrid ECU fails. It is a schematic diagram which shows an example of schematic structure of the drive system of the hybrid vehicle which concerns on a modification.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<1. Hybrid vehicle drive system>
First, the structure of the drive system 1 of the hybrid vehicle which concerns on embodiment of this invention is demonstrated.

[1-1. overall structure]
FIG. 1 is a schematic diagram illustrating an example of a schematic configuration of a drive system 1 of a hybrid vehicle according to the present embodiment. The drive system 1 includes an engine 10, a first motor generator (M / G1) 20, and a second motor generator (M / G2) 24. The engine 10, the first motor generator 20, and the second motor generator This is a power unit that can be used together with the motor generator 24 as a drive source. Specifically, the engine 10 can output a driving force for driving the driving wheels 80. The first motor generator 20 and the second motor generator 24 can independently output a driving force for driving the driving wheels 80. In the drive system 1, vehicle driving force control is performed while switching between a single motor EV traveling mode, a twin motor EV traveling mode, an engine traveling mode, and a hybrid traveling mode.

  The single motor EV travel mode is a mode in which the vehicle is driven by the output of the second motor generator 24. The twin motor EV travel mode is a mode in which the vehicle is driven by the outputs of the first motor generator 20 and the second motor generator 24. The engine travel mode is a mode in which the vehicle is driven by the output of the engine 10. The hybrid travel mode is a mode in which the vehicle is driven by at least one of the outputs of the first motor generator 20 and the second motor generator 24 and the output of the engine 10.

  The engine 10 is an internal combustion engine that generates driving force using gasoline or the like as fuel, and has a crankshaft 11 as an output shaft. The crankshaft 11 extends in the automatic transmission 30. A gear type oil pump 15 is connected to the crankshaft 11. The oil pump 15 is driven by the driving force of the engine 10 or the rotation of the driving wheels 80 and supplies hydraulic oil to the automatic transmission 30. The hydraulic fluid supplied to the automatic transmission 30 is used as hydraulic fluid that operates the CVT 31 and each clutch. The automatic transmission 30 includes a first motor generator 20, a second motor generator 24, and a continuously variable transmission (CVT) 31 as an automatic transmission.

  In addition, the oil pump 15 is not shown with respect to the shaft (for example, the motor shaft 25 of the second motor generator 24) on the drive wheel 80 side of the second transmission clutch 46, the primary shaft 34 or the secondary shaft 36 of the CVT 31. It may be connected via a gear mechanism. When the oil pump 15 is connected to the shaft closer to the drive wheel 80 than the second transmission clutch 46, the oil pump 15 can be driven by the rotation of the drive wheel 80. When the oil pump 15 is connected to the primary shaft or the secondary shaft 36, the oil pump 15 can also be driven by the rotation of the drive wheel 80 while the second transmission clutch 46 is engaged. When the oil pump 15 is coupled to the shaft closer to the drive wheel 80 than the second transmission clutch 46, the primary shaft 34 or the secondary shaft 36, the drive wheel 80 is coupled to the second transmission clutch 46 coupled to the oil pump 15. Of the side shaft, the primary shaft 34 or the secondary shaft 36, and the crankshaft 11, the crankshaft 11 is driven by the higher rotation.

  Engine 10 and first motor generator 20 are arranged in series via engine clutch 42. Between the crankshaft 11 of the engine 10 and the motor shaft 21 of the first motor generator 20, an engine clutch 42 that fastens or releases between the crankshaft 11 and the motor shaft 21 is provided. Power can be transmitted between the crankshaft 11 and the motor shaft 21 when the engine clutch 42 is in the engaged state.

  The first motor generator 20 is, for example, a three-phase AC motor, and is connected to the high voltage battery 50 via the inverter 70. The first motor generator 20 is driven using the power of the high-voltage battery 50 (powering drive) to generate a driving force of the vehicle, and is driven using the driving force of the engine 10 to generate power. And function as a generator. In other words, the first motor generator 20 can generate power using the output of the engine 10. Further, the first motor generator 20 has a function as a starter motor that starts or stops the engine 10 and a function as a motor that rotationally drives an oil pump 28 connected to the motor shaft 21.

  When the first motor generator 20 is caused to function as a starter motor, a drive motor, or a drive motor for the oil pump 28, the inverter 70 converts the DC power supplied from the high voltage battery 50 into AC power, and the first motor The generator 20 is driven. When the first motor generator 20 is caused to function as a generator, the inverter 70 converts the AC power generated by the first motor generator 20 into DC power and charges the high voltage battery 50.

  As described above, in the drive system 1 according to the present embodiment, power is transmitted between the crankshaft 11 and the motor shaft 21 not by the torque converter but by the engine clutch 42. For this reason, when the first motor generator 20 is caused to function as a drive motor, the drive power from the first motor generator 20 is consumed by the engine 10 by completely separating the first motor generator 20 and the engine 10. Thus, a decrease in efficiency of the first motor generator 20 can be suppressed.

  A gear type oil pump 28 is connected to the motor shaft 21 of the first motor generator 20. The oil pump 28 is rotationally driven by the motor shaft 21 and supplies hydraulic oil to the CVT 31 and each clutch. The oil pump 28 is configured as an electric oil pump driven by the first motor generator 20. The motor shaft 21 of the first motor generator 20 is connected to the primary shaft 34 of the CVT 31 via the first transmission clutch 44. The first transmission clutch 44 fastens or releases between the motor shaft 21 and the primary shaft 34. Power can be transmitted between the motor shaft 21 and the primary shaft 34 when the first transmission clutch 44 is in the engaged state.

  The CVT 31 has a primary shaft 34 and a secondary shaft 36 disposed in parallel to the primary shaft 34. A primary pulley 33 is fixed to the primary shaft 34, and a secondary pulley 35 is fixed to the secondary shaft 36. A winding type power transmission member 37 made of a belt or a chain is wound around the primary pulley 33 and the secondary pulley 35. The CVT 31 changes the pulley ratio by changing the wrapping radius of the power transmission member 37 on the primary pulley 33 and the secondary pulley 35, so that the CVT 31 has an arbitrary speed ratio between the primary shaft 34 and the secondary shaft 36. Transmit the converted power.

  The secondary shaft 36 is connected to the motor shaft 25 of the second motor generator 24 via the second transmission clutch 46. The second transmission clutch 46 fastens or releases between the secondary shaft 36 and the motor shaft 25. When the second transmission clutch 46 is in the engaged state, power can be transmitted between the secondary shaft 36 and the motor shaft 25. The motor shaft 25 of the second motor generator 24 is connected to the driving wheel 80 via a reduction gear and a driving shaft (not shown), so that the driving force output via the motor shaft 25 can be transmitted to the driving wheel 80. ing. The motor shaft 25 may be connected to a differential gear (not shown), and the driving force may be distributed to the front wheels and the rear wheels.

  The second motor generator 24 is connected to the engine 10 via an engine clutch 42, a first transmission clutch 44, and a second transmission clutch 46. Similar to the first motor generator 20, the second motor generator 24 is a three-phase AC motor, and is connected to the high voltage battery 50 via the inverter 70. The second motor generator 24 is driven using the power of the high-voltage battery 50 (powering drive) to generate a driving force of the vehicle, and is driven using the driving force of the engine 10 to generate power. And a function as a generator that generates power using the kinetic energy of the drive wheels 80 when the vehicle decelerates. In other words, the second motor generator 24 can generate electric power using the output of the engine 10 and can generate electric power using the kinetic energy of the drive wheels 80 during deceleration of the vehicle.

  When causing the second motor generator 24 to function as a drive motor, the inverter 70 converts the DC power supplied from the high voltage battery 50 into AC power, and drives the second motor generator 24. When the second motor generator 24 is caused to function as a generator, the inverter 70 converts the AC power generated by the second motor generator 24 into DC power and charges the high voltage battery 50. The rated output of the second motor generator 24 and the rated output of the first motor generator 20 may be the same or different.

  A low voltage battery 60 is connected via a DC / DC converter 55 to the high voltage battery 50 connected to the first motor generator 20 and the second motor generator 24 via the inverter 70. The high voltage battery 50 is a chargeable / dischargeable battery having a rated voltage of 200V, for example, and the low voltage battery 60 is a chargeable / dischargeable battery having a rated voltage of 12V, for example. The low voltage battery 60 is used as a main power source of a hybrid vehicle system. The DC / DC converter 55 steps down the voltage of the DC power of the high voltage battery 50 and supplies the charging power to the low voltage battery 60.

  The drive system 1 includes an accelerator opening sensor 95 and a vehicle speed sensor 97. The accelerator opening sensor 95 and the vehicle speed sensor 97 detect the accelerator opening and the vehicle speed, respectively, and output the detection results to each ECU. The detection result is used for processing performed by each ECU described later.

  The engine 10 is controlled by an engine control unit (engine ECU) 200. The automatic transmission 30 is controlled by a transmission control unit (transmission ECU) 300. The first motor generator 20 and the second motor generator 24 are controlled by a motor control unit (motor ECU) 400. These engine ECU 200, transmission ECU 300, and motor ECU 400 are connected to a hybrid control unit (hybrid ECU) 100 that controls the entire system in an integrated manner. The hybrid ECU 100 outputs a control command to the engine ECU 200, the transmission ECU 300, and the motor ECU 400, thereby using the engine ECU 200, the transmission ECU 300, the motor ECU 400, and the like to perform vehicle travel control or deceleration control, or the high voltage battery 50. Charge control. In drive system 1, hybrid ECU 100, engine ECU 200, transmission ECU 300, and motor ECU 400 constitute control system 900.

  According to the control system 900 according to the present embodiment, the distance that the vehicle can travel when the hybrid ECU 100 fails can be further increased by the control performed by each ECU when the hybrid ECU 100 fails. Details of the functions of each ECU when the hybrid ECU 100 fails will be described later.

  Each ECU includes a microcomputer and various interfaces or peripheral devices. Each ECU is connected to be capable of bidirectional communication via a communication line such as a CAN (Controller Area Network), for example, and communicates control information and various types of information related to the controlled object.

  Specifically, each ECU is a CPU (Central Processing Unit) that is an arithmetic processing unit, a ROM (Read Only Memory) that is a storage element that stores programs used by the CPU, operational parameters, and the like, and is used in the execution of the CPU. It is composed of a program, a RAM (Random Access Memory) that temporarily stores parameters that change as appropriate during execution thereof, and the like. Each ECU may communicate with each sensor using CAN communication. Note that the functions of each ECU according to the present embodiment may be divided by a plurality of control devices. In that case, the plurality of control devices may be connected to each other via a communication line such as CAN. Hereinafter, an outline of the function of each ECU when the hybrid ECU 100 is not malfunctioning will be described.

  The engine ECU 200 receives a control command from the hybrid ECU 100 and calculates control amounts such as a throttle opening, an ignition timing, and a fuel injection amount based on information detected by various sensors provided in the engine 10. The engine ECU 200 drives the throttle valve, spark plug, fuel injection valve, and the like based on the calculated control amount, and controls the engine 10 so that the output of the engine 10 becomes a control command value.

  Motor ECU 400 receives a control command from hybrid ECU 100 and controls first motor generator 20 and second motor generator 24 via inverter 70, respectively. The motor ECU 400 outputs a current command and a voltage command to the inverter 70 based on information such as the rotation speed, voltage, and current of each of the first motor generator 20 and the second motor generator 24, and the first motor generator 20 The first motor generator 20 and the second motor generator 24 are controlled so that the outputs of the generator 20 and the second motor generator 24 become control command values.

  The transmission ECU 300 receives the control command from the hybrid ECU 100, determines the gear ratio of the CVT 31, and controls the gear ratio to an appropriate gear ratio according to the driving state. The transmission ECU 300 controls the gear ratio of the CVT 31 by controlling the hydraulic pressure and adjusting the pulley ratio, for example. Further, the transmission ECU 300 receives a control command from the hybrid ECU 100 and controls the engine clutch 42, the first transmission clutch 44, the second transmission clutch 46, and the like according to the switching of the travel mode. The transmission ECU 300 controls connection / disconnection of each clutch by controlling the hydraulic pressure of the hydraulic oil of each clutch, for example.

  According to the control system 900 of the drive system 1, each ECU performs various controls based on a control command from the hybrid ECU 100 in a normal state in which the hybrid ECU 100 is not malfunctioning. A motor EV travel mode, an engine travel mode, and a hybrid travel mode are realized.

  In the single motor EV travel mode, the transmission ECU 300 releases all of the engine clutch 42, the first transmission clutch 44, and the second transmission clutch 46. In addition, motor ECU 400 drives second motor generator 24 via inverter 70 to output torque. Thereby, electric power is supplied from the high voltage battery 50 to the second motor generator 24 via the inverter 70. Then, the torque output from the second motor generator 24 is transmitted to the drive wheels 80 as a drive force for driving the drive wheels 80.

  In the twin motor EV travel mode, the transmission ECU 300 releases the engine clutch 42 and fastens the first transmission clutch 44 and the second transmission clutch 46. The motor ECU 400 drives the first motor generator 20 and the second motor generator 24 via the inverter 70 to output torque. Thereby, electric power is supplied from the high voltage battery 50 to the first motor generator 20 and the second motor generator 24 via the inverter 70. The torque output from the first motor generator 20 is transmitted to the motor shaft 25 via the CVT 31 and is combined with the torque output from the second motor generator 24 to drive the drive wheels 80. It is transmitted to the drive wheel 80 as force.

  In the engine running mode, the transmission ECU 300 engages all of the engine clutch 42, the first transmission clutch 44, and the second transmission clutch 46. Engine ECU 200 drives engine 10 to output torque. Thereby, the torque output from the engine 10 is transmitted to the driving wheel 80 via the CVT 31 as a driving force for driving the driving wheel 80. The engine travel mode is selected when each motor generator is malfunctioning, or when the remaining capacity SOC (State Of Charge) of the high voltage battery 50 is insufficient, for example, when normal operation is not possible. .

  In the hybrid travel mode, the transmission ECU 300 engages all of the engine clutch 42, the first transmission clutch 44, and the second transmission clutch 46. Engine ECU 200 drives engine 10 to output torque. The motor ECU 400 drives at least one of the first motor generator 20 and the second motor generator 24 via the inverter 70 to output torque. Thereby, the torque output from the engine 10 is transmitted to the motor shaft 25 via the CVT 31, and combined with the torque output from at least one of the first motor generator 20 and the second motor generator 24, The driving force for driving the driving wheel 80 is transmitted to the driving wheel 80.

  Furthermore, when starting the engine 10, the transmission ECU 300 fastens the engine clutch 42. Motor ECU 400 drives first motor generator 20 via inverter 70 and cranks engine 10 by the driving force of first motor generator 20. At this time, the transmission ECU 300 opens the first transmission clutch 44 before the engine clutch 42 is engaged so that the longitudinal vibration of the vehicle does not occur due to the differential rotation between the engine 10 and the first motor generator 20.

  The drive system 1 according to the present embodiment can generate electric power by causing the second motor generator 24 to regenerate the kinetic energy of the drive wheels 80 during deceleration of the vehicle in all the travel modes in the normal state. In the twin motor EV travel mode, the engine travel mode, and the hybrid travel mode, power can be generated by causing the first motor generator 20 to regenerate the kinetic energy of the drive wheels 80 when the vehicle decelerates. Further, in the single motor EV traveling mode and the hybrid traveling mode, the first motor generator 20 can generate electric power using a part or all of the driving force from the engine 10. Further, in the engine running mode, the first motor generator 20 can generate electric power by a part of the driving force from the engine 10.

  In the drive system 1 according to the present embodiment, the first motor generator 20 has a function as a starter motor of the engine 10. Therefore, the conventional starter motor used only when the engine 10 is started or stopped can be omitted. The first motor generator 20 is integrated with the oil pump 28 and functions as an electric oil pump. Therefore, the conventional electric oil pump that has been used only when the engine 10 or the driving wheel 80 is stopped and the hydraulic pressure cannot be generated by the gear-type oil pump 15 can be omitted.

  In the drive system 1 according to the present embodiment, the first motor generator 20 is connected to the primary pulley 33 of the CVT 31 via the first transmission clutch 44, and the first motor generator 20 is running while traveling. The generator 20 can function as a drive motor. Therefore, the power performance of the vehicle can be improved. Furthermore, while the driving force of the vehicle is generated by the engine 10, the first motor generator 20 can function as a generator when there is an excessive driving force in the output of the engine 10. Therefore, the fuel consumption performance of the vehicle can be improved.

[1-2. Functions of each ECU when hybrid ECU 100 fails]
Next, details of the functions of each ECU when the hybrid ECU 100 fails will be described.

(Engine ECU)
The engine ECU 200 drives the drive wheels 80 by causing the engine 10 to output a driving force when the hybrid ECU 100 fails. The engine ECU 200 is used for power generation by at least one of the first motor generator 20 and the second motor generator 24 in addition to the driving force used to drive the drive wheels 80 when the hybrid ECU 100 fails. The generated driving force may be output to the engine 10. Hereinafter, of the driving force output by the engine 10, the torque corresponding to the driving force used for driving the driving wheels 80 is referred to as a traveling engine torque, and the first motor generator 20 and the second motor generator 24 are Torque corresponding to the driving force used for power generation by at least one of the above is referred to as power generation engine torque.

  For example, the engine ECU 200 calculates a target value of the traveling engine torque and a target value of the power generation engine torque, and calculates the total value of the calculated target value of the traveling engine torque and the target value of the power generation engine torque. Is determined as the target value of the torque output. The engine ECU 200 controls the engine 10 so that the torque output by the engine 10 becomes the total value of the target value of the running engine torque and the target value of the power generation engine torque.

  The engine ECU 200 may calculate a target value of the traveling engine torque based on the accelerator opening. Specifically, the engine ECU 200 calculates a larger value as the accelerator opening is larger as the target value of the traveling engine torque. When the accelerator is off, the engine ECU 200 may calculate, for example, a torque for maintaining the idle rotation of the engine 10 as a target value of the traveling engine torque.

  Engine ECU 200 controls the driving force used for power generation by first motor generator 20 out of the driving force output by engine 10 when the accelerator is off when hybrid ECU 100 fails, based on the vehicle speed. Good. When the accelerator is off, transmission of power between the drive wheels 80 and the second motor generator 24 and the engine 10 is cut off by the transmission ECU 300 and the second motor generator 24 using the kinetic energy of the drive wheels 80, as will be described later. It will be possible to generate electricity by. Further, when the vehicle is decelerated, the electric power that can be generated by the second motor generator 24 by regenerating the kinetic energy of the drive wheels 80 is larger as the vehicle speed is higher. Therefore, when the vehicle is decelerated, the driving force output by the engine 10 can be appropriately reduced according to the amount of power generated by the second motor generator 24 using the kinetic energy of the drive wheels 80.

  For example, the engine ECU 200 may stop the output by the engine 10 of the driving force used for power generation by the first motor generator 20 when the accelerator is off when the hybrid ECU 100 fails, when the vehicle speed is higher than the threshold value. . The threshold value is a target value of the electric power that can be generated by the second motor generator 24 by regenerating the kinetic energy of the drive wheels 80 during deceleration of the vehicle, and that is charged to the high voltage battery 50 when the hybrid ECU 100 fails. It may be set to a value that can determine whether the vehicle speed is high enough to exceed (hereinafter also referred to as a charging target value). Further, the charging target value can be appropriately set according to various design specifications of the vehicle. Therefore, when electric power exceeding the charging target value is secured by power generation using the kinetic energy of the drive wheels 80, the driving force output from the engine 10 can be effectively reduced.

  Specifically, engine ECU 200 calculates a target value for power generation engine torque based on the vehicle speed when the accelerator is off when hybrid ECU 100 fails. For example, the engine ECU 200 calculates 0 as the target value of the engine torque for power generation when the vehicle speed is higher than the threshold value TH1 when the accelerator is off when the hybrid ECU 100 fails, and generates power when the vehicle speed is equal to or lower than the threshold value TH1. A predetermined torque greater than 0 may be calculated as the target value of the engine torque. The threshold TH1 determines whether the vehicle speed is high enough that the electric power that can be generated by the second motor generator 24 by regenerating the kinetic energy of the drive wheels 80 when the vehicle decelerates exceeds the charging target value. To a possible value.

  As will be described later, the motor ECU 400 outputs a control command to the inverter 70 so that the electric power generated by the first motor generator 20 and the second motor generator 24 exceeds the charging target value. Control the power generation. The predetermined torque that can be calculated when the vehicle speed is equal to or less than the threshold value TH1 is set so that each motor generator can generate electric power corresponding to the control command value. For example, the predetermined torque is set so that electric power exceeding the charging target value can be generated even when only power generation using the output from the engine 10 is performed. The engine ECU 200 calculates the predetermined torque as the target value of the power generation engine torque regardless of the vehicle speed when the accelerator is on when the hybrid ECU 100 fails.

  Engine ECU 200 may calculate a smaller value as the vehicle speed increases as the target value of the power generation engine torque when the accelerator is off when hybrid ECU 100 fails.

(Motor ECU)
The motor ECU 400 outputs a control command to the inverter 70 so that the electric power generated by the first motor generator 20 and the second motor generator 24 exceeds the charging target value when the hybrid ECU 100 fails. Controls the power generation of each motor generator. Specifically, the motor ECU 400 is configured so that when the hybrid ECU 100 fails, each of the electric power generated by the first motor generator 20 and the second motor generator 24 becomes a predetermined electric power higher than the charging target value. Controls the power generation of the motor generator. In addition, the motor ECU 400 calculates the ratio of the amount of power generated by the second motor generator 24 to the amount of power generated by the first motor generator 20 and the second motor generator 24, and the first motor generator 20 according to the calculated ratio. And the second motor generator 24 is controlled.

  When the hybrid ECU 100 fails, the motor ECU 400 according to the present embodiment increases the amount of power generated by the second motor generator 24 relative to the amount of power generated by the first motor generator 20 and the second motor generator 24 as the vehicle speed increases. Increase the rate. Specifically, the motor ECU 400 calculates a larger value as the vehicle speed is higher as the ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24.

  Thereby, at the time of acceleration of the vehicle, the ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24 can be increased as the vehicle speed increases. Here, as described above, when the vehicle is decelerated, the electric power that can be generated by the second motor generator 24 by regenerating the kinetic energy of the drive wheels 80 increases as the vehicle speed increases. Therefore, according to the present embodiment, as the traveling state is switched from acceleration to deceleration, the power generation by the second motor generator 24 uses the kinetic energy of the drive wheels 80 from the power generation using the output from the engine 10. The response of power generation by the second motor generator 24 when switching to power generation can be improved.

  Thus, when the vehicle is decelerated, the amount of power generated by the second motor generator 24 using the kinetic energy of the drive wheels 80 can be appropriately ensured according to the vehicle speed. Therefore, of the driving force output by the engine 10 during vehicle deceleration, the driving force used for power generation by the first motor generator 20 is reduced according to the amount of power generation by the second motor generator 24. Can be made. Therefore, when the hybrid ECU 100 breaks down, the fuel consumption can be reduced, so that the distance that can be traveled can be further increased.

  For example, when the vehicle speed is lower than the threshold value TH2, the motor ECU 400 calculates 0 as a ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24. When the ratio of the amount of power generated by the second motor generator 24 to the amount of power generated by the first motor generator 20 and the second motor generator 24 is 0, power is generated by the first motor generator 20 and the second motor Power generation by the generator 24 is limited.

  Here, when the vehicle speed is relatively low, an excessively large braking force may be applied to the drive wheels 80 by causing the second motor generator 24 to regenerate the kinetic energy of the drive wheels 80. For example, the threshold value TH2 can be appropriately set to a value lower than the threshold value TH1 from the viewpoint of preventing an excessively large braking force from being applied to the drive wheels 80 in this way.

  Further, when the vehicle speed is higher than the threshold value TH1, motor ECU 400 calculates 1 as a ratio of the power generation amount by second motor generator 24 to the power generation amounts by first motor generator 20 and second motor generator 24. When the ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24 is 1, the second motor generator 24 generates power, and the first motor Power generation by the generator 20 is limited. Thus, motor ECU 400 may stop power generation by first motor generator 20 when vehicle speed is higher than the threshold when hybrid ECU 100 fails.

  Further, when the vehicle speed is equal to or higher than the threshold value TH2 and equal to or lower than the threshold value TH1, the motor ECU 400 causes the second motor generator 24 to generate power with respect to the power generation amount by the first motor generator 20 and the second motor generator 24 as the vehicle speed increases. A value between 0 and 1 is calculated as the rate so that the rate of power generation increases. When the ratio of the amount of power generated by the second motor generator 24 to the amount of power generated by the first motor generator 20 and the second motor generator 24 is a value between 0 and 1, the first motor generator 20 and the second motor generator 20 The motor generator 24 generates power according to the ratio.

(Transmission ECU)
The transmission ECU 300 controls connection / disconnection of each clutch according to the accelerator opening when the hybrid ECU 100 fails.

  Specifically, transmission ECU 300 interrupts transmission of power from drive wheel 80 and second motor generator 24 to engine 10 when the accelerator is off when hybrid ECU 100 fails, and uses the kinetic energy of drive wheel 80. The second motor generator 24 can generate power. For example, the transmission ECU 300 fastens the engine clutch 42 and opens the first transmission clutch 44 and the second transmission clutch 46 when the accelerator is off when the hybrid ECU 100 fails. Thereby, power transmission between the drive wheels 80 and the second motor generator 24 and the engine 10 is cut off. In addition, power generation by the second motor generator 24 using the kinetic energy of the drive wheels 80 is possible. Therefore, since the efficiency of power generation by the second motor generator 24 using the kinetic energy of the drive wheels 80 can be improved when the vehicle is decelerated, the driving force output by the engine 10 is more effectively reduced. be able to.

  Transmission ECU 300 connects transmission of power between engine 10 and drive wheels 80 when the accelerator is turned on when hybrid ECU 100 fails. For example, the transmission ECU 300 fastens all of the engine clutch 42, the first transmission clutch 44, and the second transmission clutch 46 when the accelerator is turned on when the hybrid ECU 100 fails. Thereby, transmission of power between the engine 10 and the drive wheel 80 is connected.

  Transmission ECU 300 may control the transmission gear ratio of CVT 31 to be a predetermined transmission gear ratio when hybrid ECU 100 fails. The predetermined gear ratio can be appropriately set according to the output characteristics of the engine 10 when the hybrid ECU 100 fails.

<2. Operation>
Next, a flow of processing performed by the control system 900 according to the present embodiment when the hybrid ECU 100 fails will be described.

  First, with reference to FIG. 2, the flow of processing performed by the engine ECU 200 when the hybrid ECU 100 fails will be described. FIG. 2 is a flowchart illustrating an example of a flow of processing performed by the engine ECU 200 according to the present embodiment when the hybrid ECU 100 fails. As shown in FIG. 2, when the hybrid ECU 100 fails, the engine ECU 200 determines whether or not the accelerator is off (step S502). When it is not determined that the accelerator is off (step S502 / NO), the engine ECU 200 calculates a predetermined torque as a target value of the power generation engine torque (step S504).

  On the other hand, when it is determined that the accelerator is off (step S502 / YES), engine ECU 200 determines whether the vehicle speed is higher than threshold value TH1 (step S506). When it is not determined that the vehicle speed is higher than the threshold value TH1 (step S506 / NO), the engine ECU 200 calculates a predetermined torque as a target value of the power generation engine torque (step S504). On the other hand, when it is determined that the vehicle speed is higher than the threshold value TH1 (step S506 / YES), the engine ECU 200 calculates 0 as the target value of the power generation engine torque (step S508).

  Next, with reference to FIGS. 3 to 9, regarding the flow of processing performed by each ECU of the control system 900 according to the present embodiment when the hybrid ECU 100 breaks down, together with the operating state of the drive system 1 at each time explain.

  FIG. 3 is an explanatory diagram illustrating an example of transition of various state quantities when the control by the control system 900 according to the present embodiment is performed when the hybrid ECU 100 fails. 4 to 9 are explanatory diagrams for explaining the operating state of the drive system 1 at each time when the hybrid ECU 100 fails. 4-9, the broken line shows the flow of electric power, and the alternate long and short dash line shows the flow of power.

  FIG. 4 shows the operating state of the drive system 1 before time T2 in FIG. FIG. 4 shows a state where the vehicle is stopped, for example. As shown in FIG. 3, the accelerator is off before time T2. Therefore, as shown in FIG. 4, the engine clutch 42 is engaged and the first transmission clutch 44 and the second transmission clutch 46 are released by the transmission ECU 300. Thereby, transmission of power between the engine 10 and the drive wheel 80 is cut off.

  Before time T2, since the accelerator is off, engine ECU 200 calculates a torque for maintaining idle rotation of engine 10 as a target value of the running engine torque. As shown in FIG. 3, since the vehicle speed is equal to or lower than the threshold value TH1 before time T2, the engine ECU 200 calculates a predetermined torque as the target value of the power generation engine torque.

  As shown in FIG. 3, the vehicle speed is lower than the threshold value TH2 before time T2. Therefore, the motor ECU 400 calculates 0 as a ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24. As a result, as shown in FIG. 4, power generation is performed by the first motor generator 20 using the output from the engine 10, and power generation by the second motor generator 24 is limited.

  FIG. 5 shows the operating state of the drive system 1 between time T2 and time T4 in FIG. As shown in FIG. 3, at time T2, the accelerator is turned on. Therefore, as shown in FIG. 5, engine clutch 42, first transmission clutch 44, and second transmission clutch 46 are all engaged by transmission ECU 300. Thereby, transmission of power between the engine 10 and the drive wheel 80 is connected.

  Since the accelerator is on from time T2 to time T4, the engine ECU 200 calculates a value corresponding to the accelerator opening as the target value of the traveling engine torque. As a result, as shown in FIG. 3, the traveling engine torque increases from time T2 to time T4. Thereby, as shown in FIG. 5, the driving force output from the engine 10 is transmitted to the driving wheels 80 via the CVT 31. Moreover, the target value of the power generation engine torque is maintained at a predetermined torque.

  As shown in FIG. 3, the vehicle speed starts to increase at time T2, and reaches the threshold value TH2 at time T4. Therefore, the vehicle speed is lower than the threshold value TH2 from time T2 to time T4. Therefore, the motor ECU 400 calculates 0 as a ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24. Thereby, as shown in FIG. 5, the first motor generator 20 generates power using the output from the engine 10, and the power generation by the second motor generator 24 is limited.

  FIG. 6 shows an operating state of the drive system 1 at a time between time T4 and time T6 in FIG. As shown in FIG. 3, the state in which the accelerator is on is continued from time T4 to time T6. Therefore, as shown in FIG. 6, the state in which the engine clutch 42, the first transmission clutch 44, and the second transmission clutch 46 are all engaged by the transmission ECU 300 is continued.

  From time T4 to time T6, the accelerator is continuously on, so that the target value of the traveling engine torque is maintained. As a result, the traveling engine torque continuously increases after time T4. As shown in FIG. 3, the traveling engine torque is maintained at the target value until time T6 after reaching the target value. Thereby, as shown in FIG. 6, the driving force output from the engine 10 is transmitted to the driving wheels 80 via the CVT 31. Moreover, the target value of the power generation engine torque is maintained at a predetermined torque.

  As shown in FIG. 3, the vehicle speed exceeds the threshold value TH2 at time T4, and reaches the threshold value TH1 at time T6. Therefore, the vehicle speed is not less than the threshold value TH2 and not more than the threshold value TH1 from time T4 to time T6. Therefore, as the vehicle ECU speed increases, the ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24 increases as the vehicle speed increases. A value between 1 and 1 is calculated. As a result, as shown in FIG. 6, the first motor generator 20 and the second motor generator 24 generate power according to the ratio using the output from the engine 10.

  As described above, according to the present embodiment, when the vehicle is accelerated when the hybrid ECU 100 is out of order, the second power generation amount generated by the first motor generator 20 and the second motor generator 24 is increased as the vehicle speed increases. The ratio of the amount of power generated by the motor generator 24 can be increased. Thereby, when the power generation by the second motor generator 24 is switched from the power generation using the output from the engine 10 to the power generation using the kinetic energy of the drive wheels 80, the responsiveness of the power generation by the second motor generator 24 is good. Can be. Thus, when the vehicle is decelerated, the amount of power generated by the second motor generator 24 using the kinetic energy of the drive wheels 80 can be appropriately ensured according to the vehicle speed.

  FIG. 7 shows an operating state of the drive system 1 at a time between time T6 and time T8 in FIG. As shown in FIG. 3, the state in which the accelerator is on continues from time T6 to time T8. Therefore, as shown in FIG. 7, the state in which the engine clutch 42, the first transmission clutch 44, and the second transmission clutch 46 are all engaged by the transmission ECU 300 is continued.

  From time T6 to time T8, since the accelerator is continuously on, the target value of the traveling engine torque is maintained. Therefore, as shown in FIG. 3, the traveling engine torque is maintained at the target value from time T6 to time T8. Thereby, as shown in FIG. 7, the driving force output from the engine 10 is transmitted to the driving wheel 80 via the CVT 31. Moreover, the target value of the power generation engine torque is maintained at a predetermined torque.

  As shown in FIG. 3, the vehicle speed exceeds the threshold value TH1 at time T6 and continuously increases. Therefore, the vehicle speed is higher than the threshold value TH1 from time T6 to time T8. Therefore, the motor ECU 400 calculates 1 as a ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24. As a result, as shown in FIG. 7, power generation is performed by the second motor generator 24 using the output from the engine 10, and power generation by the first motor generator 20 is limited.

  FIG. 8 shows an operating state of the drive system 1 at a time between time T8 and time T10 in FIG. As shown in FIG. 3, at time T8, the accelerator is switched off. Therefore, as shown in FIG. 8, the engine clutch 42 is engaged and the first transmission clutch 44 and the second transmission clutch 46 are released by the transmission ECU 300. Thereby, power transmission between the drive wheels 80 and the second motor generator 24 and the engine 10 is cut off. In addition, power generation by the second motor generator 24 using the kinetic energy of the drive wheels 80 is possible.

  Since the accelerator is off from time T8 to time T10, the engine ECU 200 calculates a torque for maintaining the idle rotation of the engine 10 as a target value of the traveling engine torque. Thereby, as shown in FIG. 3, the traveling engine torque starts to decrease at time T <b> 8. The traveling engine torque is maintained at the torque until time T10 after reaching the torque for maintaining the idle rotation of the engine 10.

  Further, as shown in FIG. 3, the vehicle speed starts to decrease at time T8 and reaches the threshold value TH1 at time T10. Therefore, the state where the vehicle speed is higher than the threshold value TH1 continues from time T8 to time T10. Further, as described above, the accelerator is off. Therefore, 0 is calculated by the engine ECU 200 as the target value of the power generation engine torque. In other words, after time T8, the output of the engine torque for power generation by the engine 10 is stopped by the engine ECU 200.

  As described above, the state where the vehicle speed is higher than the threshold value TH1 continues from time T8 to time T10. Therefore, 1 is maintained as the ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24. Further, since the accelerator is switched off at time T8 and the vehicle starts decelerating, as shown in FIG. 8, power generation by the second motor generator 24 using the kinetic energy of the drive wheels 80 is performed after time T8. Done. On the other hand, as shown in FIG. 8, the power generation by the first motor generator 20 is limited from time T8 to time T10. Thus, the motor ECU 400 may stop the power generation by the first motor generator 20 when the vehicle speed is higher than the threshold when the accelerator is off when the hybrid ECU 100 fails.

  As described above, according to the present embodiment, when electric power exceeding the charging target value is secured by the power generation by the second motor generator 24 using the kinetic energy of the drive wheels 80, the target value of the engine torque for power generation is secured. By setting the value to 0, the driving force output by the engine 10 can be effectively reduced.

  FIG. 9 shows the operating state of the drive system 1 at a time between time T10 and time T12 in FIG. As shown in FIG. 3, the state in which the accelerator is off is continued from time T10 to time T12. Therefore, as shown in FIG. 9, the state in which the engine clutch 42 is fastened and the first transmission clutch 44 and the second transmission clutch 46 are released by the transmission ECU 300 is continued.

  Since the accelerator is kept off from time T10 to time T12, the target value of the traveling engine torque is maintained at the torque for maintaining the idle rotation of the engine 10. Therefore, during the time T10 to the time T12, the traveling engine torque is continuously maintained at the torque for maintaining the idle rotation of the engine 10.

  As shown in FIG. 3, the vehicle speed falls below threshold value TH1 at time T10, and reaches threshold value TH2 at time T12. Therefore, the vehicle speed is equal to or lower than the threshold value TH1 from time T10 to time T12. Therefore, the engine ECU 200 calculates a predetermined torque as the target value of the power generation engine torque.

  As shown in FIG. 3, the vehicle speed is not less than the threshold value TH2 and not more than the threshold value TH1 from time T10 to time T12. Therefore, as the vehicle ECU speed increases, the ratio of the power generation amount by the second motor generator 24 to the power generation amounts by the first motor generator 20 and the second motor generator 24 increases as the vehicle speed increases. A value between 1 and 1 is calculated. As a result, as shown in FIG. 9, power is generated by the first motor generator 20 using the output from the engine 10. In addition, power is generated by the second motor generator 24 using the kinetic energy of the drive wheels 80. The first motor generator 20 and the second motor generator 24 generate power according to the ratio.

  As described above, according to the present embodiment, when the vehicle decelerates when the hybrid ECU 100 fails, the second power generation amount generated by the first motor generator 20 and the second motor generator 24 is reduced as the vehicle speed decreases. The ratio of the amount of power generated by the motor generator 24 can be reduced. Thereby, when the vehicle is decelerated, the braking force applied to the drive wheels 80 can be appropriately adjusted according to the vehicle speed. Therefore, it is possible to prevent an excessively large braking force from being applied to the drive wheel 80.

  After time T12, the state where the accelerator is off continues. Further, at time T12, the vehicle speed falls below the threshold value TH2. Therefore, after time T12, the vehicle speed is lower than the threshold value TH2. Therefore, the operation state of the drive system 1 after time T12 is the operation state shown in FIG.

<3. Modification>
In the drive system 1 described above, the motor shaft 25 of the second motor generator 24 is connected to the secondary shaft 36 via the second transmission clutch 46, but the arrangement of the second motor generator 24 is related. It is not limited to examples. Hereinafter, the drive system 2 according to a modified example in which the arrangement of the second motor generator 24 is different from that of the drive system 1 will be described.

  FIG. 10 is a schematic diagram illustrating an example of a schematic configuration of the drive system 2 of the hybrid vehicle according to the modification. In the drive system 2 according to the modification, the arrangement of the second motor generator 24 is different from that of the drive system 1 described with reference to FIG. Further, unlike the drive system 1, the drive system 2 according to the modification does not include the second transmission clutch 46. As shown in FIG. 10, in the modification, the motor shaft 25 of the second motor generator 24 is connected to the primary shaft 34, and the driving force output via the motor shaft 25 can be transmitted to the primary shaft 34. It has become. The secondary shaft 36 is connected to the drive wheel 80 via a reduction gear and a drive shaft (not shown) so that the driving force output through the secondary shaft 36 can be transmitted to the drive wheel 80. Hereinafter, various drive modes realized in the normal state in which the hybrid ECU 100 is not broken down by the drive system 2 according to the modification will be described.

  In the modification, in the single motor EV travel mode, the transmission ECU 300 opens the engine clutch 42 and the first transmission clutch 44. In addition, motor ECU 400 drives second motor generator 24 via inverter 70 to output torque. Thereby, electric power is supplied from the high voltage battery 50 to the second motor generator 24 via the inverter 70. The torque output from the second motor generator 24 is transmitted to the secondary shaft 36 via the CVT 31 and is transmitted to the drive wheels 80 as a drive force for driving the drive wheels 80.

  In the modification, in the twin motor EV traveling mode, the transmission ECU 300 releases the engine clutch 42 and fastens the first transmission clutch 44. The motor ECU 400 drives the first motor generator 20 and the second motor generator 24 via the inverter 70 to output torque. Thereby, electric power is supplied from the high voltage battery 50 to the first motor generator 20 and the second motor generator 24 via the inverter 70. The torque output from the first motor generator 20 and the second motor generator 24 is transmitted to the secondary shaft 36 via the CVT 31 and is transmitted to the driving wheel 80 as a driving force for driving the driving wheel 80. Is done.

  In the modification, in the engine running mode, the transmission ECU 300 engages the engine clutch 42 and the first transmission clutch 44. Engine ECU 200 drives engine 10 to output torque. Thereby, the torque output from the engine 10 is transmitted to the secondary shaft 36 via the CVT 31, and is transmitted to the drive wheel 80 as a drive force for driving the drive wheel 80.

  In the modification, in the hybrid travel mode, the transmission ECU 300 engages the engine clutch 42 and the first transmission clutch 44. Engine ECU 200 drives engine 10 to output torque. The motor ECU 400 drives at least one of the first motor generator 20 and the second motor generator 24 via the inverter 70 to output torque. Thereby, the torque output from the engine 10 is transmitted to the secondary shaft 36 via the CVT 31, and combined with the torque output from at least one of the first motor generator 20 and the second motor generator 24, The driving force for driving the driving wheel 80 is transmitted to the driving wheel 80.

  Next, an operation state of the drive system 2 according to the modified example when the control by the control system 900 described above is performed when the hybrid ECU 100 fails will be described.

  In the modification, the engine clutch 42 is engaged and the first transmission clutch 44 is released by the transmission ECU 300 when the accelerator is off when the hybrid ECU 100 fails. Thereby, power transmission between the drive wheels 80 and the second motor generator 24 and the engine 10 is cut off. In addition, power generation by the second motor generator 24 using the kinetic energy of the drive wheels 80 is possible.

  The engine ECU 200 may cause the engine 10 to output a driving force used for power generation by the first motor generator 20. In that case, the driving force output from the engine 10 is transmitted to the motor shaft 21 via the engine clutch 42, and power generation can be performed by the first motor generator 20. Further, the kinetic energy of the drive wheel 80 is transmitted to the motor shaft 25 via the CVT 31. The second motor generator 24 may generate power using the kinetic energy. The power generation by the first motor generator 20 and the second motor generator 24 is controlled by the motor ECU 400 as described above.

  In the modification, the engine clutch 42 and the first transmission clutch 44 are engaged by the transmission ECU 300 when the accelerator is turned on when the hybrid ECU 100 fails. Thereby, transmission of power between the engine 10 and the drive wheel 80 is connected. The engine ECU 200 drives the engine 10 and outputs a driving force for driving the driving wheels 80. Thereby, the driving force output from the engine 10 is transmitted to the secondary shaft 36 via the CVT 31 and transmitted to the driving wheel 80.

  In addition, engine ECU 200 causes engine 10 to output a driving force used for power generation by at least one of first motor generator 20 and second motor generator 24. Since the driving force output from the engine 10 is transmitted to the motor shaft 21 via the engine clutch 42, power generation can be performed by the first motor generator 20. Further, since the driving force output from the engine 10 is transmitted to the motor shaft 25 via the primary shaft 34, power generation can be performed by the second motor generator 24. The power generation by the first motor generator 20 and the second motor generator 24 is controlled by the motor ECU 400 as described above.

<4. Conclusion>
As described above, according to the present embodiment, when the hybrid ECU 100 breaks down, the motor ECU 400 increases the second power generation amount by the first motor generator 20 and the second motor generator 24 as the vehicle speed increases. The ratio of the amount of power generated by the motor generator 24 is increased. Therefore, as the driving state is switched from acceleration to deceleration, the power generation by the second motor generator 24 is switched from power generation using the output from the engine 10 to power generation using the kinetic energy of the drive wheels 80. The responsiveness of power generation by the second motor generator 24 can be improved. Thereby, when the vehicle is decelerated, the amount of power generated by the power generation using the kinetic energy of the drive wheels 80 can be appropriately ensured according to the vehicle speed. Therefore, of the driving force output by the engine 10 during vehicle deceleration, the driving force used for power generation by the first motor generator 20 is reduced according to the amount of power generation by the second motor generator 24. Can be made. Therefore, when the hybrid ECU 100 breaks down, the fuel consumption can be reduced, so that the distance that can be traveled can be further increased.

  In the above description, an example in which the vehicle drive system 1 according to the present embodiment includes two motor generators has been described. However, the technical scope of the present invention is not limited to such an example. For example, the present invention can be applied to a vehicle including three or more motor generators.

  Further, the processing described using the flowchart in the present specification may not necessarily be executed in the order shown in the flowchart. Some processing steps may be performed in parallel. Further, additional processing steps may be employed, and some processing steps may be omitted.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can make various modifications or application examples within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

1, 2 Drive system 10 Engine 11 Crankshaft 15 Oil pump 20 First motor generator (M / G1)
21 Motor shaft 24 Second motor generator (M / G2)
25 Motor shaft 28 Oil pump 30 Automatic transmission 31 Continuously variable transmission (CVT)
33 Primary pulley 34 Primary shaft 35 Secondary pulley 36 Secondary shaft 37 Power transmission member 42 Engine clutch 44 First transmission clutch 46 Second transmission clutch 50 High voltage battery 55 DC / DC converter 60 Low voltage battery 70 Inverter 80 Drive wheel 95 Accelerator opening sensor 97 Vehicle speed sensor 100 Hybrid control unit (hybrid ECU)
200 Engine control unit (engine ECU)
300 Transmission control unit (transmission ECU)
400 Motor control unit (motor ECU)
900 Control system

Claims (5)

An engine control unit for controlling an engine capable of outputting a driving force for driving the drive wheels;
A first motor generator capable of generating electric power using the output of the engine, and a second motor capable of generating electric power using the output of the engine and generating electric power using the kinetic energy of the driving wheels during deceleration of the hybrid vehicle A motor control unit for controlling the generator;
A hybrid control unit that outputs a control command to the engine control unit and the motor control unit;
Including
The engine control unit drives the driving wheels by causing the engine to output a driving force when the hybrid control unit fails.
When the hybrid control unit fails, the motor control unit has a ratio of the amount of power generated by the second motor generator to the amount of power generated by the first motor generator and the second motor generator as the vehicle speed increases. Increase,
Hybrid vehicle control system.   When the accelerator is turned off when the hybrid control unit fails, the transmission of power between the drive wheel and the second motor generator and the engine is cut off, and the second motor generator using the kinetic energy of the drive wheel The control system for a hybrid vehicle according to claim 1, further comprising a transmission control unit that enables power generation by the vehicle.   Based on the vehicle speed, the engine control unit uses a driving force used for power generation by the first motor generator among driving forces output by the engine when the accelerator is off when the hybrid control unit fails. The hybrid vehicle control system according to claim 2, wherein the control system controls the hybrid vehicle. When the vehicle speed is higher than a threshold when the accelerator is turned off when the hybrid control unit fails,
The motor control unit stops power generation by the first motor generator;
The engine control unit stops the output by the engine of the driving force used for power generation by the first motor generator;
The hybrid vehicle control system according to claim 3. A first motor generator capable of generating electric power using an output of an engine capable of outputting a driving force for driving the driving wheels; and generating electric power using the output of the engine; and A motor control unit for controlling a second motor generator capable of generating electric power using kinetic energy,
The drive wheel is driven by the output of the engine when an engine control unit that controls the engine and a hybrid control unit that outputs a control command to the motor control unit fail.
When the hybrid control unit fails, the motor control unit has a ratio of the amount of power generated by the second motor generator to the amount of power generated by the first motor generator and the second motor generator as the vehicle speed increases. Increase,
Motor control unit.

Images