Online energy management for intermittent operation of hybrid electric vehicles

Commonly, the control of hybrid electric vehicles (HEVs) is focused on efficiency maximization by distributing engine and electrical machine power. The only state to be considered in such an optimization is the battery charge. In certain situations such as cold starts in winter additional aspects gain importance. Passenger safety and comfort require sufficient heating of the cabin which drains thermal energy from the engine. Moreover, exhaust aftertreatment systems must be heated up fast in order to comply with emission limits. This becomes even more critical for short-haul cold start scenarios. In this paper, we propose a possible solution based on an online model predictive controller (MPC) to balance fuel consumption and emission minimization with thermal management which is shown to provide significant emission reduction compared to purely powertrain centered approaches.