基于三角函数正交性的永磁伺服系统机械参数辨识

Identification of Mechanical Parameters of Permanent Magnet Servo System Based on Orthogonal Characteristics of Trigonometric Function

为抑制永磁伺服系统机械参数不确定对系统控制性能的影响,提出一种利用三角函数正交性进行机械参数辨识的方法。给电机施加两个不同幅值、相同角频率的机械角速度指令,通过正弦、余弦函数在不同区间内的积分实现系统摩擦系数与转动惯量的解耦,在提高辨识精度的同时消除了不定负载转矩对黏滞摩擦系数、库仑摩擦系数和转动惯量辨识结果的影响。利用辨识得到的机械参数值对负载转矩进行观测,并针对系统的摩擦转矩、负载转矩进行对应的前馈补偿。仿真和实验结果均验证了该方法的有效性,机械参数辨识误差在1%左右,进行前馈补偿后转速环的控制性能得到一定的提升。

To mitigatethe impact of uncertain mechanical parameters on the control performance of apermanent magnet servo system,a method of mechanical parameter identification using the orthogonality of trigonometric functions is proposed.This method applies two mechanical angular velocity commands with different amplitudes but the same angular frequency to the motor.Itdecouples the friction coefficient and moment of inertia of the system through the integration of sine and cosine functions in different intervals,enhancing identification accuracy and eliminating uncertainty.The effect of load torque on the identification results of viscous friction coefficient,Coulomb friction coefficient and moment of inertia is investigated.At the same time,the load torque is observed by using the mechanical parameter values obtained from the identification,and the corresponding feed-forward compensation is performed for the friction torque and load torque of the system.The simulation and experimental results have verified the effectiveness of the method,with a mechanical parameter identification error of about 1%.The control performance of the speed loop is improved to a certain extent after the feed-forward compensation.