多轴轮毂电机驱动电动车电子差速控制研究

Electronic Differential Control of Multi-axle Wheel-Hub Motor Driven Electrical Vehicles

针对现阶段电动轮驱动车辆电子差速控制无法适应任意行驶工况、电机性能要求较高等问题,提出自适应电子差速控制策略;对轮毂电机进行转矩指令控制,转速随动的方式,使车轮根据自身受力状态实现差速;同时介绍了多轴轮毂电机驱动汽车动力学整车建模方法。在此基础上,介绍整体控制策略,模拟传统汽车从动力系统到差速器的功率分配特性,利用驾驶员期望车速和反馈的实际车速的差值输入到PID控制器中,输出得到各电机目标需求转矩。最后提出差速性能评价方法,并针对差速问题的3种主要工况进行离线仿真及台架试验。结果表明:所提自适应电子差速控制能够控制车轮理论和实际行驶距离误差小于0.5%左右,验证了自适应电子差速控制策略的正确性以及较高的控制精度。

Aiming at the problem that the electronic differential control of electric wheel driven vehicle can t adapt to any driving conditions and the higher requirements of motor performance at this stage,a self-adaptive electronic differential control was carried out.The wheel-hub motor was controlled by torque command and speed follow-up,so that the wheel could realize differential speed according to its stress state.At the same time,the modeling method of multi-axis wheel-hub motor driven vehicle dynamics was introduced.On the basis,the overall control strategy was introduced to simulate the power distribution characteristics of the traditional vehicle from the power system to the differential.The difference between the driver s expected speed and the feedback actual speed was input into the PID controller to output the target torque of each motor.Finally,the differential evaluation method was proposed,and the off-line simulation and HIL test were carried out for the three main conditions of differential problems.The results show the proposed self-adaptive electronic differential control can control the theoretical and actual driving distance error of the wheel less than 0.5%,which verifies the correctness of the electronic differential control strategy and the high control accuracy.