基于H2/H∞优化的微纳卫星饱和姿态控制器设计

摘要

This paper concerns the robust performance and input saturation problem for attitude control of a microsatellite, and presents a novel method for design of PID saturation attitude controllers for microsatellites based on the mixed H2/H∞ optimization. The method takes account of the problem that the pointing accuracy of microsatellites is vulnerable to space environmental disturbances and the intemal uncertainty of moment-of-inertia variation due to its smaller size and weight,and considers the saturation problem of control actuators for its physical configuration and energy confinement, and the input uncertainty for the installation error of the actuator could also deteriorate the performance of the attitude control system, so the anti-interference performance of the attitude control system can be effectively improved. For a PID controller is feasible for spacecraft attitude control, the mixed H2/H∞ performance index was used to optimize the parameters of robust anti-interferential PID saturation attitude controller for microsatellites. The simulation results demonstrate that the presented controller can improve the robustness and the dynamic response performance, and the input saturation can be effectively refused.%针对微纳卫星的鲁棒抗饱和姿态控制问题,提出了一种新的基于混合H2/H∞优化的PID饱和姿态控制器设计方法.该方法不仅考虑了空间环境干扰力矩和星体转动惯量不确定性对姿态控制系统的影响,而且考虑了由于物理结构的限制和能量消耗的限制带来的输入饱和问题以及由执行机构安装误差和输入干扰导致的输入不确定性问题,因而能够有效地提高姿态控制系统的抗干扰能力.设计了鲁棒多目标优化抗干扰饱和姿态稳定PID控制器,并基于线性矩阵不等式对其进行了求解.仿真结果比较表明,基于H2/H∞优化的微纳卫星姿态饱和PID控制器可显著提高系统的鲁棒性及动态响应性能,有效避免控制器增益饱和现象.