Aiming at solving the battery electric vehicle (BEV) problems of high energy
consumption and low efficiency in heating at low temperature, this study takes
the thermal management system of BEV as the research object and develops an
integrated thermal management control system based on heat pump air-conditioning
for BEV. First, the functional requirements and optimal operating temperature
range of each BEV subsystem are defined. Second, on the basis of the
thermodynamic cycle principle of the air-conditioning system and compared with
the traditional positive temperature coefficient thermistor (PTC) heating mode,
the high heating efficiency and low energy consumption advantages of the heat
pump system in winter are highlighted. Third, combined with the special
structural characteristics of BEV, a hybrid heating scheme (i.e., heat pump
system + PTC) is proposed, and a “motor/electronic control system waste heat
recovery” scheme is formulated to realize the secondary recovery of energy.
Fourth, the functional mode of the integrated vehicle thermal management scheme
is divided, its working circuit is determined, and then its work priority rules
are established. Finally, the control strategy models of the key components of
the system are established using MATLAB/Simulink, while the thermal management
system model is built using AMESim. The application environment scenarios are
set, and the efficiency of the system under different temperatures is simulated
and analyzed to verify the effectiveness of the developed system. Results show
that the developed system has a significant effect, effectively reducing the
energy consumption when the vehicle starts the thermal management system at low
temperature while improving the vehicle efficiency. Thus, this research
contributes to the improvement and application of the heating system of BEVs at
low temperature.
