Abstract: A vehicle includes a start switch, an engine, and a first motor-generator coupled to a rotation shaft of the engine. Upon an operation of the start switch, the first motor-generator accelerates a rotational speed of the output shaft of the engine with a torque which decreases as a rotational speed of an output shaft of the first motor-generator increases.

Abstract: An ECU executes a program including the steps of: executing fuel-cut control when an IG OFF operation has been performed and a vehicle is traveling; determining torque command values of a first MG and a second MG when a charge power upper limit value Win is reduced; controlling the first MG based on the determined torque command value of the first MG; and controlling the second MG based on the determined torque command value of the second MG.

Abstract: A vehicle is provided with a differential gear including a sun gear, a carrier, and a ring gear, motor generators coupled to the sun gear, an engine coupled to the carrier, and a wheel coupled to the ring gear. The vehicle includes an ECU that stops the engine upon operation of a start switch by a driver, and a brake that brakes the sun gear upon operation of the start switch while the vehicle is traveling.

Abstract: An ECU executes a program including the steps of: executing fuel-cut control when an IG OFF operation has been performed and when a vehicle is traveling; executing deceleration control when vehicle speed is equal to or higher than a threshold value; ending the deceleration control and permitting restart of an engine when the vehicle speed has become lower than the threshold value; and controlling a first MG and the engine when an IG ON operation has been performed.

Abstract: An ECU executes a program including the steps of carrying out low-load control when an IG OFF operation is performed, when a vehicle is running, and when stop of an engine is not permitted, carrying out gate cut-off control, ending low-load control and gate cut-off control when a brake pedal has been operated, when a vehicle speed is lower than a threshold value, or when a prescribed time period has elapsed since the IG OFF operation, permitting stop of the engine, and carrying out fuel cut control.

Abstract: An ECU executes a program including the steps of carrying out fuel cut control when an IG OFF operation is performed and when a vehicle is running, setting a target value Net for an engine rotation speed Ne, carrying out control of a first MG, and ending control of the first MG when a vehicle speed becomes lower than a prescribed vehicle speed.

Abstract: There is provided a control device for a vehicle that includes: a driving force source; a hydraulic transmission; and an interrupting mechanism that is able to interrupt power transmission from the driving force source to a drive wheel. The control device includes a controller that is configured to, after the driving force source is stopped while the vehicle is travelling, on the condition that a hydraulic pressure applied to the transmission has decreased, execute control for setting a speed ratio of the transmission to a predetermined low speed ratio, such as a high-speed gear in the case where a low-speed gear and the high-speed gear are provided, while the vehicle is travelling.

Abstract: A hybrid vehicle of the invention has an engine, a planetary gear unit including a carrier linked with rankshaft of the engine and a ring gear linked with a drive shaft, a motor MG1 inputting and outputting power to and from a sun gear of the planetary gear unit, and a motor MG2 inputting and outputting power to and from the drive shaft. During a drive of the hybrid vehicle in a light load state and under a drive restriction of the motor MG2, the hybrid vehicle corrects a target revolution speed Ne* of the engine to make a calculated average charge-discharge electric power Wbave of a battery equal to a charge-discharge electric power demand Wb*, while keeping a torque of the engine unchanged (steps S300 to S330), and controls actuation of the engine and the motors MG1 and MG2.

Abstract: In response to a system-off instruction, the drive system control technique of the invention controls individual motors of an electric cooling water pump and an electric cooling fan to stop (step S100), waits for elapse of a preset reference time period since start of the control of stopping the motors (step S110), and turns off a relay to disconnect a supply of electric power from a battery to a CPU of a control unit (step S120). Inactivation of the relay after elapse of the preset reference time period since start of the control of stopping the motor disconnects the supply of electric power to the control unit in the state of sufficiently low back emf generated by the motors. This arrangement effectively prevents malfunction of the control unit due to the back emf generated by the motors.

Abstract: The technique of the invention sets an upper limit torque Tm1max and a lower limit torque Tm1min output from a motor generator, based on input and output restrictions Win and Wout of a battery, a motor electric power demand Pm2, an auxiliary machinery electric power demand Pcsm, and a potential loss Ploss (step S150). The technique then restricts a target revolution speed Ne* of an engine to make an output torque of the motor generator within a range of the lower limit torque Tm1min to the upper limit torque Tm1max (steps S180 to S200). This arrangement ensures output of a torque in response to a driver's requirement, while effectively preventing the battery from being charged or discharged excessively.

Abstract: In response to a decrease in observed battery voltage Vb to or below a preset threshold value Vs1, the control procedure of the invention closes the gates of an inverter for an air conditioner to stop a supply of electric power to the air conditioner (at a time point t1). In response to a further decrease in observed battery voltage Vb to or below a preset threshold value Vm1, the control procedure closes the gates of inverters for motors MG1 and MG2 to stop supplies of electric power to the motors MG1 and MG2 (at a time point t2). The threshold values Vs1 and Vm1 are set to keep the battery voltage Vb at or above a minimum required voltage for proper operations of an electric power steering (EPS). This arrangement guarantees the minimum required voltage for proper operations of the EPS and accordingly ensures the stable steering performance even in the event of a voltage decrease of the battery.

Abstract: An ECU performs a program including a step of notifying a system main relay shut-off signal to a high-voltage system using equipment when a system main relay shut-off demand due to a HV system failure is generated, a step of shutting off the system main relay when a high voltage shut-off acknowledging signal from the high-voltage system using equipment is not unreceived, a step of shutting off the system main relay when a high voltage shut-off acknowledging signal from the high-voltage system using equipment is unreceived and a current value in a high voltage circuit is more than the predetermined threshold, and a step of shutting off the system main relay when the current value in the high voltage circuit is not more than the predetermined threshold and the predetermined period of time has elapsed from the occurrence of a HV system malfunction.

Abstract: In response to a system-off instruction, the drive system control technique of the invention controls individual motors of an electric cooling water pump and an electric cooling fan to stop (step S100), waits for elapse of a preset reference time period since start of the control of stopping the motors (step S110), and turns off a relay to disconnect a supply of electric power from a battery to a CPU of a control unit (step S120). Inactivation of the relay after elapse of the preset reference time period since start of the control of stopping the motor disconnects the supply of electric power to the control unit in the state of sufficiently low back emf generated by the motors. This arrangement effectively prevents malfunction of the control unit due to the back emf generated by the motors.

Abstract: An ECU performs a program including a step of notifying a system main relay shut-off signal to a high-voltage system using equipment when a system main relay shut-off demand due to a HV system failure is generated, a step of shutting off the system main relay when a high voltage shut-off acknowledging signal from the high-voltage system using equipment is not unreceived, a step of shutting off the system main relay when a high voltage shut-off acknowledging signal from the high-voltage system using equipment is unreceived and a current value in a high voltage circuit is more than the predetermined threshold, and a step of shutting off the system main relay when the current value in the high voltage circuit is not more than the predetermined threshold and the predetermined period of time has elapsed from the occurrence of a HV system malfunction.

Abstract: In response to a decrease in observed battery voltage Vb to or below a preset threshold value Vs1, the control procedure of the invention closes the gates of an inverter for an air conditioner to stop a supply of electric power to the air conditioner (at a time point t1). In response to a further decrease in observed battery voltage Vb to or below a preset threshold value Vm1, the control procedure closes the gates of inverters for motors MG1 and MG2 to stop supplies of electric power to the motors MG1 and MG2 (at a time point t2). The threshold values Vs1 and Vm1 are set to keep the battery voltage Vb at or above a minimum required voltage for proper operations of an electric power steering (EPS). This arrangement guarantees the minimum required voltage for proper operations of the EPS and accordingly ensures the stable steering performance even in the event of a voltage decrease of the battery.

Abstract: A hybrid vehicle of the invention has an engine, a planetary gear unit including a carrier linked with rankshaft of the engine and a ring gear linked with a drive shaft, a motor MG1 inputting and outputting power to and from a sun gear of the planetary gear unit, and a motor MG2 inputting and outputting power to and from the drive shaft. During a drive of the hybrid vehicle in a light load state and under a drive restriction of the motor MG2, the hybrid vehicle corrects a target revolution speed Ne* of the engine to make a calculated average charge-discharge electric power Wbave of a battery equal to a charge-discharge electric power demand Wb*, while keeping a torque of the engine unchanged (steps S300 to S330), and controls actuation of the engine and the motors MG1 and MG2.

Abstract: The technique of the invention sets an upper limit torque Tm1max and a lower limit torque Tm1min output from a motor generator, based on input and output restrictions Win and Wout of a battery, a motor electric power demand Pm2, an auxiliary machinery electric power demand Pcsm, and a potential loss Ploss (step S150). The technique then restricts a target revolution speed Ne* of an engine to make an output torque of the motor generator within a range of the lower limit torque Tm1min to the upper limit torque Tm1max (steps S180 to S200). This arrangement ensures output of a torque in response to a driver's requirement, while effectively preventing the battery from being charged or discharged excessively.