Research on the overall efficiency optimization-based power management strategy of the two-mode PSHEV

Parallel-Series Hybrid Electric Vehicles (PSHEV) can enhance the fuel economy by adjusting the engine operating points, and take full advantage of the high efficiency of the mechanical transmission. Based on the power-split scheme and the analysis of the power component efficiency, the identification method of overall efficiency is proposed. The dynamic efficiency model of the power-coupled machine is discussed in emphases. The overall efficiency optimization model for power management is established for enhancing the system total efficiency. The optimization calculation and implement are carried on by system simulation, and the test results indicate that the overall efficiency optimization method can control the operating points of the power components at the comprehensive optimal states, and the system transmission efficiency and the fuel economy are enhanced observably. The research of the power-split characteristic analysis and the overall efficiency optimization provides foundation for developing the control strategy and control system of PSHEV.