存在多输入未建模动态的鲁棒控制

Robust Control of Nonlinear System with Multi-Input Unmodelled Dynamics

研究了一类存在输入未建模动态的非线性鲁棒控制问题,就M.Krstic得出的动态非线性抑制引理提出了一种推广方案,将原引理只适用于单输入的情况,推广到多输入的情况,并将其应用在某型号飞机的非线性控制律设计中,仿真结果表明,在舵机存在未建模动态时,该方案能明显抑制未建模动态对飞机动态造成得影响,从而增强飞机控制系统的鲁棒性。

The dynamic nonlinear damping theory of Krstic et al^() can only solve the problem of robust control of nonlinear system with single-input unmodelled dynamics. But practical problems generally involve multi-input dynamics. We aim to extend the theory of Krstic et al to cover the case of multi-input dynamics and then apply it to designing control law of a practical aircraft. We state the conditions under which the extension of the theory of Krstic et al is valid and then give proof of the extension. And then we design a nonlinear flight control law based on feedback linearization theory and extended dynamic nonlinear damping theory. The result of simulation shows that this scheme can counteract the effect of the unmodelled dynamics on condition that there is unmodelled dynamics occurring at the aircraft actuator, and moreover improve the robustness of the flight control system.