A hybrid vehicle propulsion system including, an internal combustion engine, a torque converter including a lockup clutch the torque converter having an input and an output, the input coupled to the internal combustion engine, an electric energy conversion device coupled downstream of the torque converter output, and a control system for adjusting torque output of the hybrid propulsion system, the control system adjusting the torque output of the electric energy conversion device during a torque converter lockup clutch engagement transition event.