电动助力转向系统传感器的容错控制及仿真分析

Fault Tolerant Control of Electric Power Steering System Sensor and Its Simulation Analysis

通过分析EPS系统的动力学模型,得出转向柱的输出扭矩(扭矩传感器的测量值)、电机的有效输出扭矩和地面反作用力之间的关系。当扭矩传感器失效时,通过后两者近似计算出转向柱的输出扭矩,并用巴特沃思滤波器对估计值进行处理,消除白噪声对系统的影响。应用Matlab/Simulink软件对EPS容错控制系统进行仿真分析。结果表明:此估计值可以较为精确地反映传感器的测量值;在传感器发生故障时,EPS容错控制系统利用传感器估计值保持了控制系统的稳定性,从而提高了汽车的操纵稳定性和行驶安全性。

By means of analyzing the dynamic model of EPS system, the paper obtained the relationship among output torque of the steering column, effective output torque of the motor and ground reaction torque. When the torque sensor fails, it calculated the approximate output torque of the steering column by way of both in the latter, and processed the estimate value with the Butterworth filter in order to eliminate the white noise of the system. Finally by use of Matlab/Simulink software, it made the simulation of fault-tolerant control system. The simulation results show that the estimate can reflect the sensor measurement accurately. In the case of sensor failure, EPS fault-tolerant control system can use the estimated value of the sensor to maintain the stability of control system so as to improve the car handling-stability and driving-safety.