Drivetrain Design And Optimization Of Control Strategy For Hybrid Electric Vehicles

Hybrid Electric Vehicles (HEVs) combine the advantages of conventional engine-driven vehicles and pure Electric Vehicles (EVs). This provides satisfied driving performance and lower exhaust emission. Thus, HEV is a feasible solution to solve the energy crisis and environmental pollution problems.Performances of HEVs, in terms of driving, fuel consumption, and exhaust emission, strongly depend on the coordination of the drivetrain and their control strategy. In this paper, the classification and associated characteristics of HEVs are firstly analyzed and discussed. And then, the configuration and operation modes of electric assist parallel HEVs are introduced. A design method of drivetrain for electric assist parallel HEVs are presented, in which .both the weight and rate power of the drivetrain components are comprehensively considered. By analyzing the characteristics and energy flow principles of its drivetrain, a modeling method based on experimental data is proposed. The feasibility of the method is confirmed by experimental data of NiMH battery. The proposed simulation method for HEVs drivetrain do not include the complicated differential equations calculation but would be practical for evaluating the driving performance and fuel consumption quickly by integrating the configured components of the drivetrain. Furthermore, an optimal real-time control strategy with the minimal equivalent fuel consumption for the electric assist HEVs is proposed in the paper, which considers the vehicle driving performance, fuel consumption, and the SOC of battery. The study of this paper would be helpful to reduce the period of design for HEVs and supply the reference for drivetrain design, control strategy and vehicle's performance evaluation.