具有输入饱和的近空间飞行器鲁棒控制

针对近空间飞行器这一类存在外部扰动,输入饱和和参数不确定的多输入多输出线性系统,提出了一种基于干扰观测器的抗饱和鲁棒控制方案.将干扰观测器与抗饱和控制技术相结合,从而消除系统存在的未知外部扰动、输入饱和和不确定性对系统控制的影响.首先,设计干扰观测器对线性外部系统产生的未知扰动进行估计.然后根据干扰观测器输出,通过超前抗饱和方法设计抗饱和补偿器,并将其加入到鲁棒控制器的设计中,保证闭环系统存在输入饱和、未知外部扰动和参数不确定情况下的稳定性.为便于设计,干扰观测器、抗饱和补偿器和控制器设计矩阵均通过求解线性矩阵不等式得到.最后,将提出的鲁棒抗饱和控制方法应用于近空间飞行器,仿真结果验证了该控制方案的有效性.

Robust control for near space vehicles with input saturation

An anti-windup robust control scheme is proposed for the near space vehicles (NSV) which are a class of multi-input multi-output (MIMO) linear systems with input saturation, unknown external disturbances and parametric uncertainties. The developed anti-windup control scheme is cooperated with disturbance observer to eliminate the effects of input saturation, unknown external disturbances and parametric uncertainties. A disturbance observer is presented to estimate the unknown disturbance generated by a linear exogenous system. Then, based on the output of the disturbance observer, the anticipatory anti-windup compensator is developed and considered with the robust controller design to ensure the stability of the close-loop system subject to unknown external disturbances, input saturation and parametric uncertainties. The designed gain matrices of the disturbance observer, anti-windup compensator and robust controller are determined by solving the linear matrix inequalities (LMIs). Finally, the proposed anti-windup robust control scheme is applied to the NSV, and the effectiveness of this developed control scheme is illustrated by the simulation results.