转台在遥感测试领域中有着广泛的应用, 同时对其控制效果的要求也越来越高, 尤其对于低速大惯量转台的控制。针对由于转动惯量估计不准、扰动模型不确定等因素造成系统模型不能被准确描述, 经典状态观测器无法准确观测出系统状态的问题, 提出了不依赖于精确系统模型的扩张状态观测器来跟踪反馈系统中不确定因素的作用量。首先对扩张状态观测器进行了分析和设计, 构建了非线性PID控制器的仿真结构框图, 并将系统在Simulink下进行了仿真模拟。试验结果表明, 该方法使转台低速稳速精度相对于传统PID控制提高了8. 6%, 跟踪误差下降为原来的13. 3%, 有效提高了低速大转矩转台控制系统的性能。

Turn is widely applied in the remote sensing test field, and the requirements for its control performance become increasingly high, especially for the control of low-speed, large -torque turn. To the problems that the classical state observer is unable to detect the system state precisely and it is hard to accurately describe the system model due to inaccurate estimation of rotational inertia and uncertain perturbation model, we proposed a control method based on Extended State Observer (ESO) to track the action of uncertainties, which is independent of the exact system model. Firstly, the ESO was analyzed and designed. Then, a nonlinear PID controller for speed loop was constructed, and simulation was made to the system under the Simulink. Results of the test show that the method can improve the performance of the control system of the low-speed, large-torque turn effectively. Compared with the traditional PID control, the accuracy of steady speed of the turn was improved by 8. 6%, and the tracking error was reduced by 13. 3%.