Drive force control for hybrid electric vehicle

A hybrid electric vehicle comprising:

• an accelerator pedal;
• an engine consuming fuel in order to output a rotating torque;
• a first motor connected to the engine, the first motor generating electric power in response to the rotating torque of the engine while generating a rotating torque to accelerate the engine in response to power supply;
• a second motor generating a drive torque for the vehicle in response to power supply;
• a power storage device connected electrically with the first motor and the second motor, the power storage device supplying power to the first motor and the second motor while accumulating power generated by the first motor;
• means for determining a depression amount of the accelerator pedal;
• means for determining a rotation speed of the engine;
• means for setting a target drive torque for the vehicle in response to the depression amount of the accelerator pedal;
• means for supplying power corresponding to the target drive torque to the second motor from the power storage device;
• means for calculating an available power supply amount to the first motor by subtracting a power supply amount to the second motor from an available output power of the power storage device;
• means for calculating a target rotation speed of the engine based on the target drive torque;
• and
• means for supplying power to the first motor from the power storage device within a range which does not exceed the available power supply amount to the first motor, when the available power supply amount to the first motor is a positive value and the target rotation speed of the engine exceeds the rotation speed of the engine.

A control method for a hybrid electric vehicle, the hybrid electric vehicle comprising an accelerator pedal, an engine consuming fuel in order to output a rotating torque, a first motor connected to the engine, the first motor generating electric power in response to the rotating torque of the engine while generating a rotating torque to accelerate the engine in response to power supply, a second motor generating a drive torque for the vehicle in response to power supply, and a power storage device connected electrically with the first motor and the second motor, the power storage device supplying power to the first motor and the second motor while accumulating power generated by the first motor, the method comprising:

• determining a depression amount of the accelerator pedal;
• determining a rotation speed of the engine;
• setting a target drive torque for the vehicle in response to the depression amount of the accelerator pedal;
• supplying power corresponding to the target drive torque to the second motor from the power storage device;
• calculating an available power supply amount to the first motor by subtracting a power supply amount to the second motor from an available output power of the power storage device;
• calculating a target rotation speed of the engine based on the target drive torque;
• and
• supplying power to the first motor from the power storage device within a range which does not exceed the available power supply amount to the first motor, when the available power supply amount to the first motor is a positive value and the target rotation speed of the engine exceeds the rotation speed of the engine.