可重构飞行控制系统的滑模自适应控制律设计

Design of a Sliding Mode Adaptive Control Law for Reconfigurable Flight Control System

当飞行控制系统操纵面发生损伤故障时,结合自适应思想,采用滑模控制方法进行重构飞行控制系统的设计。采用单位向量法设计滑模控制器,这种控制器由线性部分和非线性部分组成。线性部分采用改进的线性二次型最优控制器法进行计算,而非线性部分采用自适应增益来更好地适应故障情况。利用某型飞机的纵向飞行控制系统模型进行仿真,结果表明,带有自适应增益的滑模控制方法不仅适合于正常情况下的飞控系统设计,而且对操纵面损伤故障情况具有较强的适应能力,与固定增益情况相比,具有更好的跟踪效果和重构控制效果。

In the case of loss-of-effectiveness failure of aircraft control surface, a sliding mode control scheme is adopted for the reconfigurable flight control system design. A unit vector approach is applied for sliding mode controller, which is composed of both linear and nonlinear components. A modified linear quadratic optimal controller is designed for the linear part, while adaptive gain is used in the nonlinear part for adapting to different control surface damages. Simulation was carried out for the reconfignrable flight control system of an aircraft longitudinal model. The simulation results show that the sliding mode control method with adaptive gain is not only suitable for the design of flight control system under normal conditions, but also is adaptive to the control surface damages. Compared with the fixed gain controller, the adaptive controller has better model following and reconfigurable performances.