纯电动汽车电动助力转向模糊控制策略研究

Research on fuzzy PID control strategy of electric power steering in pure electric vehicle

助力电机和减速装置是纯电动汽车电动助力转向系统(EPS)的核心部件,由于机构本身的惯量以及摩擦阻尼等因素影响EPS系统的转向性能,针对EPS系统响应慢、回正控制不灵敏的问题,提出一种基于模糊控制策略的控制方法来减小EPS系统的回正阻力,从而改善EPS系统的转向性能。其中,建立了EPS系统数学模型,对在实时行驶工况下纯电动汽车的EPS系统电机电流、电机转矩、方向盘转矩为控制对象,为了验证该控制策略的可行性,搭建了纯电动汽车EPS系统硬件在环实验环境,实验结果表明,所采用的模糊PID控制策略能很好的改善实时工况下的EPS系统转向性能。

Electric motor and reducer are the core components of electric power steering system of pure electric vehicles,due to the performance of institutional inertia and friction damping factors of the EPS system,the EPS system has the problems of slow response and returning not sensitively,proposing a control method of the fuzzy PID control strategy based on EPS system in order to reduce the back steering resistance,so as to improve the performance of EPS system.Among them,the establishment of the mathematical model of EPS system,the real-time driving conditions of pure electric vehicle EPS system of motor current,motor torque and wheel torque control with fuzzy PID control strategy,in order to verify the feasibility of the control strategy,building the pure electric vehicle EPS system hardware in the loop(HIL)test environment,Test results show that fuzzy PID control strategy adopted by the EPS.It also can improve the steering performance of EPS system under real-time driving condition.