Integrated energy and thermal management for hybrid electric heavy duty trucks

This paper proposes an integrated energy and thermal management (IETM) strategy for parallel hybrid electric heavy duty trucks. This supervisory control strategy is developed based on the equivalent consumption minimization strategy (ECMS) to optimize both the power split (between the internal combustion engine (ICE) and electric machine) and the heating/cooling power for the battery pack. The method takes into account the concept of State of Function (SOF) describing the capability of the battery as function of State of Charge (SOC) and temperature. Simulation results show the dependence of the global fuel consumption with respect to ambient temperature. Situations are identified where the losses for battery heating/cooling are larger than the benefits from the hybrid powertrain. Hence, an integrated approach between energy and thermal management is needed.