Hybrid electric vehicle control strategy to achieve maximum wide open throttle acceleration performance

A control system for a powersplit hybrid electric vehicle PSHEV powertrain powered by at least one of an engine, a traction motor, and a generator motor comprising:

• an accelerator position sensor;
• a vehicle speed sensor;
• a PRNDL position sensor;
• a battery for powering the traction motor and generator motor and receiving power from the generator motor;
• and
• a vehicle system control (VSC) to control the vehicle powertrain, the VSC
• receiving input from the accelerator position sensor, vehicle speed sensor, and PRNDL position sensor
• making a determination of whether full forward acceleration is requested,
• making a determination of whether the engine is running, estimating the sum torque of the traction motor and the generator motor if the engine is not running,
• calculating the maximum sum torque output of the traction motor and the engine,
• comparing the estimated sum torque of the traction motor and the generator motor with the calculated sum torque output of the traction motor and the engine, and
• starting the engine if the estimated sum torque of the traction motor and the generator motor is less than the calculated sum torque output of the traction motor and the engine for a given vehicle speed.