Patent ID: 7268442

Claim:
A method for estimating power of an engine in a powertrain for a hybrid electric vehicle to determine desired driving torque at vehicle traction wheels, the powertrain having a motor, a generator and gearing that drivably couples the engine, the motor and the generator, the method comprising the steps of: computing a current motor torque in repetitive time samples; computing a current generator torque in repetitive time samples; computing a desired traction wheel torque as a function of the current motor torque and the current generator torque at a given instant in a repetitive time sampling; and computing estimated engine power as a function of the generator torque and the motor torque computed at an earlier instant in the time sampling whereby engine power accuracy is improved during operation of the powertrain with transient changes in the desired traction wheel torque; the estimated engine power being computed by determining an initial raw estimate of engine power, the method further comprising the step of calculating upper and lower limits for the value of the initial raw estimate of engine power.