不同控制策略下新能源汽车跨临界 CO₂ 热泵最优运行特性

For the transcritical CO₂ automotive heat pump system, the main factors affecting the optimal discharge pressure were investigated under different control strategies. The simulation model was established based on the GT-Suite simulation platform and calibrated with experimental data of heat production performance. A constant supply air temperature was used to constrain the heating capacity. The optimal discharge pressure was simulated numerically at different ambient temperatures, different supply air temperatures and different air volumes, and then compared with the constant speed control mode. The results show that there is no optimal discharge pressure in the constant speed control mode; the optimal discharge pressure increases with increasing indoor air volume, increasing ambient temperature and increasing outlet air temperature in the constant supply air control mode. The air supply temperature affects the optimal discharge pressure variation by 13.09%; the ambient temperature affects the optimal discharge pressure variation by 9.64%; the air volume affects the optimal discharge pressure variation by 5.95%. The optimal discharge pressure correlation formula is proposed based on the simulation data.