Research On Electroic Differential Control Of Driving Wheel

With the rapid development of economics and the automotive industry in China, the number of vehicles is increasing at a very high speed. But the increase gives a great tension to the environment and traffic safety. Electric vehicle (EV) technology is a combined technology, which includes automatic control,electric and vehicle engineering, It is valued all over the world. Electrical differential is the important part of the drive control, which plays an important role in promoting the improvement of EV. This paper that takes front-wheel drive EV as a research object includes theoretic and practical study is based on the control of electrical differential of EV, which has some realistic significance in some relative fields.Electric control system is the core technology in electronic differential system. In this article, the main analysis and study are supposed to be electric control system. Based on study of theory of motor drive, the relative matters are all analyzed in detail, which such as contains establishment of motor dynamic equation and transfer function, law of closed loop PID control, and the modification of PID parameter that based on fuzzy control applied in digital PID control method.Analysis of strategy of electronic differential system control is also analyzed in detail. In this part, hardware actuator, control system and steering principle are clearly explained. With analysis of Ackerman-Jeantan's steering model, the velocity of each wheel that is altered with change of angle in course of electronic differential is calculated. Moreover, coherence of velocity of driving wheel at an even pace, and operation mode of deceleration, acceleration and even pace are studied, which in order to establish strategy of electronic differential when turning.In last part of this paper, the parameters of mechanic structure and electric system of designed electric vehicle are described. Feasibility and reliability in designed project are testified, which based on statistics from the trial of digital drive control system in prototype of electric vehicle, and statistics and figures from calculation of parameters of electronic differential when vehicle make a turn.