Exergy-informed collaborative control of refrigerant-based integrated thermal management systems for electric vehicles

• Design of a refrigerant-based integrated thermal management system architecture. • The collaborative control strategy achieved active cooling capacity distribution. • Enabling good temperature control and energy efficiency. • Exergy analysis was used to guide improvements of control strategies. Refrigerant direct cooling (RDC) faces significant challenges in uneven cooling capacity distribution and strong cabin-battery thermal coupling, which limits its widespread application in integrated thermal management systems (ITMS). To address this issue, this study proposes an ITMS architecture based on dual evaporators and variable opening valves (VOVs), and develops a collaborative control strategy for the compressor and VOVs incorporating exergy analysis. A numerical model of the ITMS was established to quantitatively evaluate the thermal and energy consumption characteristics under different control strategies. Results indicate that, compared with compressor control, the collaborative control strategy achieves active cooling distribution and significantly mitigates subsystem coupling effects. Based on the main sources of exergy destruction identified through exergy analysis, directions for optimizing the control strategy are provided. The improved strategies suppress the battery temperature rise, reduce the battery temperature difference, and maintain the maximum cabin temperature fluctuation within 0.56 °C. Compared to the baseline control strategy, the improved strategies achieve a maximum COP increase of 44.83% and a maximum system exergy destruction reduction of 52.6%. This study validates the feasibility and engineering value of exergy analysis-based collaborative control in enhancing system energy efficiency and decoupling multi-heat source management.