Research and Analysis on the Energy Consumption Test Methods of Plug-In Hybrid Electric Vehicles Under High and Low Temperature Environments

To support the national “dual carbon” goals and improve the evaluation standard system for new energy vehicle energy consumption, this study selects 24 plug-in hybrid electric vehicles (PHEVs) from different platforms to conduct World Light Vehicle Test Cycle (WLTC) based energy consumption and charge-sustaining tests under high and low-temperature environments. The research systematically investigates the impact of temperature extremes on PHEV energy consumption. Results show that most vehicles exhibit effective energy management in charge-depleting (CD) mode, with more than half still meeting the 4% energy balance criterion under both high and low temperatures. In charge-sustaining (CS) mode, the proportion of ineffective vehicles is higher under low-temperature cold starts and high-temperature hot starts, while the effectiveness decreases for high-temperature cold starts. It is recommended to moderately relax the validity assessment criteria for high-temperature conditions and further standardize the hot start test protocol. This study provides theoretical support and empirical data for improving PHEV energy consumption testing standards and formulating low-carbon strategies for the industry.