Study On The Adaptive Starting Control Strategy Of Pure Electric Vehicle

Pure electric vehicle starting control technology as an major part of the vehicle control technologies,and its core and difficulty is the control of motor output torque in the process of starting.In order to make the vehicle can start smoothly in different road conditions,and meet the standard of starting performance requirements,the key is how to control the motor output torque in the start process of PEV.So the research on the development of pure electric vehicle technology has certain theoretical value and practical engineering significance.In this paper,based on the task group project of " Research on Control Function of Vehicle Controller for Pure Electric Vehicle",considering the structural characteristics of the electric vehicle and imitating the idle crawling function of the traditional vehicle,a control strategy that the compensation of starting torque of pure electric vehicle is put forward.The main work of this paper is as follows:(1)First of all,the pure electric vehicle type power system structure characteristics are summarized.Compared with the traditional fuel vehicle and PEV power system drive performance differences,and summed up the characteristics of the traditional vehicle idle crawling performance.Based on the above research,a function of the pure electric vehicle automatic start control that have intelligent control features is presented.Through analyzing and discussing the starting dynamics of the object and the basic principle of speed control,the control focus of the speed control system is obtained.Also,the starting control scheme based on the starting torque adaptive compensation is worked out,and the evaluation index of the automatic starting quality is summarized.(2)In order to improve the ride comfort,safety and take full account of driver’s intuitive driving experience in the actual road driving test.Combined with the traditional vehicle idling crawl features,and based on the application of the Longberg algorithm to the slope estimation scheme,two starting torque compensation control strategies are proposed which are fuzzy PID algorithm and incremental PI algorithm.(3)Using AVL Cruise and MATLAB/Simulink joint simulation method,the simulation model of vehicle and the control model of the slope estimation and start algorithm are established,and the accuracy of the vehicle simulation model is verified by the dynamic test.Through the simulation experiment of the slope estimation algorithm and the starting control strategy,and the influence of the two strategies on the starting quality under different starting conditions is compared and analyzed.(4)According to the comparison results of the initial performance simulation test,the adaptive torque compensation control strategy based on incremental PI algorithm is proposed finally.And carried out a pure electric prototype road test,the results show that during the start of the road and ramps,the prototype can sart quickly andsmoothly.What’s more,the experimental results are in good agreement with the simulation results.