Control Algorithms for xEV Powertrain Efficiency and Thermal Comfort

This paper investigates how different on-board energy management system (EMS) algorithms can affect the total energy consumption considering propulsion, heating, ventilation, and air conditioning (HVAC) operation and thermal comfort requirements. Firstly, an integrated plug-in hybrid electric vehicle (PHEV) powertrain and HVAC model including vehicle cabin has been developed as a demonstrator. Two different EMS algorithms - namely a rule-based and an equivalent consumption minimization strategy (ECMS) one - are applied to the integrated PHEV model and evaluated under different environmental conditions. The results showed that the HVAC system operation affects the total energy consumption benefits when ECMS algorithm is used over the rule-based. ECMS reduces the total energy consumption by 2.5% compared to rule-based without HVAC operation, while the total energy consumption reduction changes to 5.3% and 6.3% when HVAC provides heating and cooling power respectively. Furthermore, the ECMS algorithm can reach the target of sufficient thermal comfort 1 minute earlier than rule-based in WLTC cycle. Based on the above findings we recommend evaluating the EMS algorithms with integrated propulsion and the HVAC system modeling. By applying it to real EMS unit energy consumption reduction of new vehicles under real-world operating conditions can be expected.