Study On Dual-Energy Storage System Design And Simulation For Pure Electric Vehicle

Electric vehicle will lead the future direction of vehicle development.It will be important content of "Twelveth Five-Year plan" and "863Project" in China.With the advantage of high efficiency, low noise and little pollution emission, pure electric vehicle (PEV) are leading a revolution in automobile industry under the pressure of the natural environment portection and the growing oil shortage nowadays.So far, inadequate driving range is still the major fencing to hinder the development of PEV,new efforts are necessary to improve the usage efficiency and regenerative braking recycling for limited energy available.Supported by a project of "Research on key technologies of core components of pure electric vehicle and industrial exploration", this dissertation mianly focuses on the PEV issues like electric drive system,regenerative braking,dual-energy system (DESS),and optimization&control strategies of PEV.Specifically, the mian work and contributions of the dissertation are summarized as follows:1. Regarding to the dual-requirements for high-energy density and high-power density,the DESS is designed to be a compodition of battery and ultra-capacitor plus bi-direction DC/DC converter in parallel. The mian-loop circuit of DESS is constructed,and the working states are analyzed. After analyzing the power and energy requirements,the structure and parameters of DESS are presented in term of mathematical computation.Finally,a forementioned results are verified by extending ADVISOR simulator with dual-energy storage auto-sizing.2. According to the different runing states of PEV,the fuzzy self-tuning control strategy for bi-directional DC/DC converter is designed. In regenerative braking state, the converter is used to provide constant charging current for the battery and ultra-capacitor. The simulation model of DC/DC converter is estalished in Matlab,and the simulation results prove that the controling method is correct and effective.3. In order to improve the performance of braking force distribution and energy management, two fuzzy optimal control strategies are proposed for PEVwith DESS. A simulation w.r.t. economical effciency,power parameter,power efficiency and braking energy is performed. The results show that the proposed fuzzy strategies can more effectively distribute the output power of DESS, improve the property in DESS, and attain a better acceleration and economic performance.4. A softwave platform with friendly onterface specialized for the simulation of the pure electric vehicle(PEV) with DESS is established by the redevelopment of ADVISOR. The new platform overcomes the shortcoming that ADVISOR can not be simulate DESS’s performance. Combined with typical cycle cinditions,the performance simulation is performed for PEV with DESS and control strategies. The simulation results show that both the dynamic property and the economical effciency of the PEV with DESS are improved.