Study on the Impact of Thermal Management System and Heat Utilization Strategy on Energy Consumption of Electric Vehicles Under Low-Temperature

Abstract

Aiming at the problem of the low driving mileage retention rate and high energy consumption for thermal management of the battery electric vehicles under low temperature, this paper establishes the energy management system model and compares the energy consumption performance of the heat pump with motor waste heat utilization and the PTC heater under low temperature through simulation analysis. The results show that the energy consumption of heat pump system is positively correlated with the energy transfer efficiency of the heat flow path, and negatively correlated with the motor efficiency and the thermal load of the cabin. This paper further analyzes the operating efficiency trends of the two systems under different working conditions, and optimizes the thermal management strategy according to the ambient temperature and thermal demand. The results show that the energy consumption of the vehicle could be reduced by enabling the heat pump system and the PTC heater to operate within the high-efficiency region. Under the temperature of −20 ℃, the vehicle driving mileage with the optimized strategy is increased by 6.2% compared with the original strategy.