Simulation Study On Hybrid Energy Storage System Used In Electric Vehicle

Recently years, as the global environment and the energy status is becoming more and more serious, new energy vehicles especially electric vehicles causes wide concern in the limelight. But now vehicle power batteries have many shortcomings such as “charging slow” and “low efficiency”. This situation restricted the development and popularization of electric vehicles in a certain extent. On the other hand, the single power system can't satisfy the energy demand of the electric vehicles at this stage, so hybrid energy storage system(HESS) becomes a more effective way to solve this problem. The object of study in this paper is based on a miniature HESS vehicle which built by our research group. Modeling, simulation and control strategy of power distribution is discussed in paper. Research the effect of the improvement of HESS and compared with the single power system.Firstly, the operating principle and characteristic of battery, super capacitor and DC/DC convertor is analyzed in paper. After that their principles is discussed combine with ADVISOR simulation models through each equivalent circuits, and the accuracy of the models based on the simulation results is checked.Secondly, the control principles of based on logic threshold control strategy and based on the vehicle speed of the power distribution control strategy is introduced, then established simulation models in Simulink. Through a variety of operating models to research their power distribution effect and use the control strategy of based on logic threshold to distribute the motor power in HESS.Thirdly, through a variety of operating modes for vehicle simulation experiment, the parameters of HESS based on the test platform vehicle is matched. Compared with the results of single power system, HESS decreases the energy consumption, and the efficiency of the vehicle is improved.Finally, based on the parameters and simulation results, the HESS test platform vehicle is established. The key subsystems and the space of HESS test platform vehicle is designed before construct the four-wheel independent drive test platform vehicle.