以虚拟轮胎与地面间的相互作用力为思路,构建由电动助力转向系统、转向阻力矩加载装置及测控系统组成的车辆电动助力转向系统(EPS)试验平台,研究车辆转向工况的准确模拟方法。设计双闭环实时控制策略,以提高力矩加载装置伺服电机的力矩输出精度,并从软件、硬件层面设计伺服电机防超程控制策略,以保障试验平台应用过程的安全性。对某乘用车原地转向工况进行EPS试验平台模拟试验,并对试验平台控制系统的实时性进行硬件在环试验,结果表明,设计开发的控制系统及其控制算法能够满足实时性、准确性要求,实现了车辆转向工况在EPS试验平台上的准确模拟,可为车辆EPS控制器的开发、调试提供良好的试验环境。
To realize accurate simulation of vehicle steering conditions, we established an EPS test-bed consisting of an electric power steering system, steering resistance torque loading device and measurement control system on the basis of the virtual interactive force between the tire and the ground. A double closed loop real-time control strategy was designed for improving the output precision of the servo motor torque. An anti-overrun control strategy was designed from software and hardware levels to guarantee security of the application process of the test platform. The simulation test of the EPS test platform was carried out on a vehicle in situ steering condition, and the hardware-in-the-loop experiment was carried out to verify the real-time performance of the experimental platform control system. The results show that the designed control system and control algorithm meet the real-time and accuracy requirements of simulation of vehicle steering conditions, and are able to provide a good test environment for development and debugging of EPS controllers.