Research On Regenerative Braking Contorl Strategy For Pure Electric Vehicle

With the whole world focus on the energy problem, governments introduce policies to support for pure electric vehicle. One of the core issues, which affects the development of pure electric vehicle, is how to let people drive it more far with just one charging. Therefore regenerative braking control strategy becomes more important.According to the energy storage type of regenerative braking system for pure electric vehicle, regenerative braking control strategy in multi constraints is studied thoroughly.First of all, this paper studies the regenerative braking torque distribution strategy,which is based on automobile ECE regulations. It emphasizes the effect of braking force strength and the ground adhesion coefficient on theallocation strategy. The simulation results show that: when in the light braking, braking torque is provided by the regenerative braking torque completely. And when in electro-mechanical brake mode, the front wheel share 88.7% braking force, which accounts for about 52.8% of the regenerative braking force. In deep braking process, the regenerative braking isn’t considered.Secondly, on the basis of the regenerative braking torque distribution strategy, this paper studies the temperature, SOC, the rate of charge and the charge current of the battery and other constraints on the impact of the regenerative braking control,innovation proposed an estimation method of battery SOC based on Adaptive Calman filter and a current control strategy of battery charging, and make a simulation of the strategy, the simulation results show that: in the actual working condition, the estimation of the battery SOC is at around 3%, the current control error is less than 3%, which greatly improved the application of the battery SOC estimation and current control in practical engineering.According to the above constraints,this paper proposed a regenerative braking control strategy under multiple constraint conditions.Finally, the paper selected 4 common conditions: NYCC(new york comic con),UDDS(Urban Dynamometer Driving Schedule), EUDC_LOW(low speed conditions of European city), HWFET(Highway Fuel Economy Test). Based on the MATLAB and Advisors, this paper has made the combined simulation of the above four kinds of working conditions for regenerative braking control strategy under multipleconstraint conditions.The simulation results show that: in the above four conditions,the efficiency of Regenerative braking energy feedback can reach 32.2% at most, Improved energy recovery efficiency.