摘要:
A hybrid powertrain system includes an internal combustion engine (14) operatively connected to a second torque machine (72) to transmit torque to an output member (64). A method for operating the hybrid powertrain system includes monitoring an operator torque request, determining an output torque command based upon the operator torque request, commanding a transition between an engine-off state and an engine-on state, monitoring an engine crank angle, spinning the engine unfueled, estimating cylinder pressure based upon the engine crank angle during the spinning of the engine (14), predicting a cylinder pulse torque based upon the cylinder pressure, determining a cancellation torque for the second torque machine (72) based upon the predicted cylinder pulse torque, and controlling motor torque output from the second torque machine (72) based upon the cancellation torque and the output torque command.