| Abstract:In order to further clarify the effects of the high flexibility of the engine operation strategy on the economic efficiency of range extender electric vehicles, and to clarify the potential enhancement in overall vehicle performance resulting from the optimization of the engine performance，based on the GT-SUITE simulation platform, a detailed energy flow analysis of different engine working strategies was provided in the study, including line operating conditions and points operating conditions on vehicle economy. A comparative analysis was undertaken to assess the overall vehicle performance before and after optimizing the engine combustion system. The results indicate that the vehicle fuel consumption per kilometer is more optimal when the engine operates under points operating conditions，based on the China Light Vehicle Test Cycle (CLTC). In comparison to the fuel consumption observed under line operating conditions, the consumption can be reduced to 0.03824 L/km based on points operating conditions. However, the adoption of the strategy of operating the engine at the optimal efficiency point of the range extender system is relatively singular, hindering improvements in vehicle fuel economy and resulting in a degradation of 0.81% compared to the optimal value. Following the optimization of engine performance, greater power output of the engine is achieved in the efficient operating region, leading to an overall improvement in vehicle fuel efficiency. The optimal fuel consumption is reduced from 0.03824 L/km to 0.03664 L/km. |