Achieving environmental governance and energy poverty alleviation requires high-efficiency and environmental-friendly thermal management systems for electric vehicles. This study developed and tested an integrated R290 (propane) vapor-injection (INJ) heat pump system with waste heat recovery in a cold climate. Dual secondary loops are adopted considering the flammability of the R290 refrigerant. Experimental results reveal that the INJ system outperforms the basic (BAS) system by 12.1% in coefficient of performance (COP) and 36.3% in heating capacity at âˆ’20 Â°C/20 Â°C (out-cabin/in-cabin) ambient temperature. The INJ mode with 1 kW waste heat recovery can provide a 29.8% improvement in heat capacity and a 7.4% increase in COP compared to that with no waste heat at âˆ’20 Â°C/20 Â°C. This study provides experimental support for achieving efficient operation of automotive heat pump systems under a wide operation temperature range.
Keywords electric vehicles, thermal system, heat pump, R290, vapor injection, secondary loop