陀螺稳定平台速度环的离散自抗扰控制

针对陀螺稳定平台在高精度定位下的控制精度受到速度环电机在低速运动时非线性摩擦力影响的问题,文章设计了一种改进策略的自抗扰控制器,将原系统中的非线性摩擦力与电机不同转向时的模型误差统一视为系统扰动,采用扩张状态观测器对这个扰动进行估计,前馈到控制量中进行校正。理论分析了一阶离散系统上扩张状态观测器的推导过程和稳定性条件,并采用遗传算法工具箱对针对平台所设计的扩张状态观测器的参数进行辨识。在仿真实验中,我们首先分析了所设计的扩张状态观测器的开环性能,然后将所设计的自抗扰控制器与实际系统采用的PI控制器的控制精度进行了对比分析。文章为进一步提高陀螺稳定平台的控制性能,提供了一种新的高精度的控制策略。

Discrete Active Disturbance Rejection Control of Velocity Loop in Gyro-stabilized Platform

The control performance of the gyro-stabilized platform is affected by the nonlinear friction of the velocity loop motor at low speed. Therefore, an improved active disturbance rejection control is designed to solve this problem. We combine the nonlinear friction with the model error as the disturbance of the system, and design an discrete extended state observer（ESO） to estimate the system disturbance, then the estimated disturbance is fed into the control system to be corrected. We theoretically analyze the derivation and stability conditions of the ESO in first-order discrete system, and use the genetic algorithm toolbox to identify the parameters of the ESO. In the simulation experiment, we first analyze the open-loop performance of the ESO, then compare the control precision of PI controller and the designed active disturbance rejection control system. This paper provides a new high-precision control strategy for further improving the control performance of the gyro-stabilized platform.