METHOD OF DECELERATING A VEHICLE WITH REGENERATIVE AND FRICTION BRAKING

摘要

A method of decelerating a vehicle equipped with both regenerative powertrain braking from a motor/generator and friction braking from fluid pumped through a brake circuit. A deceleration demand is received, and regenerative braking torque is ramped up in response to the deceleration demand. The brake circuit is pre-charged during the ramping up of regenerative braking torque. Pre-charging the brake circuit includes pumping fluid to at least one wheel cylinder braking device to reduce the required pump speed and resulting noise for any subsequent braking demand on the brake circuit. The pump is actuated to operate at a predetermined speed that maintains noise and vibration below predetermined levels.