Research on the Efficiency of the Dual-Mode Hybrid Vehicle

摘要

The dual-mode power-split-type hybrid transmission system is a typical multi-input and -output system, hence the efficiency analysis is complicated compared with conventional vehicles. In this chapter, a comprehensive efficiency model of the dual-mode hybrid vehicle is built on the basis of power loss analysis, including the engine fuel conversion power loss, the charge/discharge power loss of the battery pack and the coupling mechanism power losses. The exact model of the coupling system is investigated considering the motor loss, gear spin loss, clutch/brake loss, bearing loss and sealing loss. Besides, a control strategy is further developed to achieve the optimal system efficiency by selecting the engine operation point and the power of the battery pack. The simulation results show that the new strategy can greatly improve the fuel economy of the vehicles.