Hybrid vehicle and control method thereof

A hybrid vehicle that is equipped with an internal combustion engine and a motor and is driven with power output from at least the motor to a drive shaft, said hybrid vehicle comprising:

• a heating module that uses the internal combustion engine as a heat source to warm up a passenger compartment;
• a fuel consumption priority instruction module that gives a fuel consumption priority instruction for giving preference to fuel consumption, in response to an operator's request;
• a temperature measurement module that measures either of temperature of the internal combustion engine and temperature of a medium, which depends on the temperature of the internal combustion engine, and sets the measured temperature to a control temperature;
• a power demand setting module that sets a power demand required for the drive shaft;
• an intermittent operation permission module that, in response to no reception of the fuel consumption priority instruction given by said fuel consumption priority instruction module during heating of the passenger compartment by said heating module, gives permission for intermittent operation of the internal combustion engine upon condition that the control temperature measured by said temperature measurement module is not lower than a preset first temperature, while otherwise placing a prohibition on the intermittent operation of the internal combustion engine,
• in response to reception of the fuel consumption priority instruction given by said fuel consumption priority instruction module during heating of the passenger compartment by said heating module, said intermittent operation permission module giving permission for the intermittent operation of the internal combustion engine upon condition that the control temperature measured by said temperature measurement module is not lower than a preset second temperature, which is below the preset first temperature, while otherwise placing the prohibition on the intermittent operation of the internal combustion engine;
• and
• a control module that, in response to the permission for the intermittent operation of the internal combustion engine given by said intermittent operation permission module, controls the internal combustion engine and the motor to ensure an output power level corresponding to the power demand to the drive shaft with the intermittent operation of the internal combustion engine,
• in response to the prohibition on the intermittent operation of the internal combustion engine placed by said intermittent operation permission module, said control module controlling the internal combustion engine and the motor to ensure the output power level corresponding to the power demand to the drive shaft with continuous operation of the internal combustion engine.

A control method of a hybrid vehicle, which is equipped with an internal combustion engine, a motor, a heating module that uses the internal combustion engine as a heat source to warm up a passenger compartment, and a fuel consumption priority instruction module that gives a fuel consumption priority instruction for giving preference to fuel consumption, in response to a operator's request, said hybrid vehicle being driven with power output from at least the motor to a drive shaft,

• said control method comprising the steps of:
• (a) setting a power demand required for the drive shaft;
• (b) measuring a cooling water temperature in the internal combustion engine;
• (c) in response to no reception of the fuel consumption priority instruction given by said fuel consumption priority instruction module during heating of the passenger compartment by said heating module, giving permission for intermittent operation of the internal combustion engine upon condition that the cooling water temperature measured in said step (b) is not lower than a preset first temperature, while otherwise placing a prohibition on the intermittent operation of the internal combustion engine,
• in response to reception of the fuel consumption priority instruction given by said fuel consumption priority instruction module during heating of the passenger compartment by said heating module, giving permission for the intermittent operation of the internal combustion engine upon condition that the cooling water temperature measured in said step (b) is not lower than a preset second temperature, which is below the preset first temperature, while otherwise placing the prohibition on the intermittent operation of the internal combustion engine;
• and
• (d) in response to the permission for the intermittent operation of the internal combustion engine given in said step (c), controlling the internal combustion engine and the motor to ensure an output power level corresponding to the power demand to the drive shaft with the intermittent operation of the internal combustion engine,
• in response to the prohibition on the intermittent operation of the internal combustion engine placed in said step (c), controlling the internal combustion engine and the motor to ensure the output power level corresponding to the power demand to the drive shaft with continuous operation of the internal combustion engine.