Development of an integrated energy management strategy with cabin heating for plug-in hybrid electric vehicle

In this study, an integrated powertrain-thermal energy management strategy (IEMS) was proposed for a power-split type plug-in hybrid electric vehicle. Dynamic models of the powertrain components including the engine, motor/generator, power-split transmission and battery were obtained with a thermal management system consisting of an engine (thermal part), radiator, positive temperature coefficient (PTC) heater, heater core and cabin. Using the powertrain and thermal management system model, a performance simulator was developed and simulation results of the powertrain components, engine coolant temperature and the cabin temperature were compared with the vehicle dynamometer test results. Based on the powertrain and thermal management system characteristics, an IEMS was proposed that considers not only the battery SOC, but also the ratio of PTC heater power consumption to battery power consumption. The simulation results of the IEMS were compared with the existing energy management strategy (EMS) and the IEMS improved fuel economy over EMS.