A method for controlling a hybrid powertrain system including an internal combustion engine includes controlling operation of the hybrid powertrain system in response to a preferred minimum coolant temperature trajectory for the internal combustion engine.
GOVERNMENT CONTRACT RIGHTS
This invention was made with U.S. Government support under Agreement No. DE-FC26-08NT04386 awarded by the U.S. Department of Energy. The U.S. Government may have certain rights in this invention.