基于μ理论的飞机俯仰姿态控制

Airplane Pitch Attitude Control Based on μ Theory

摘要:

针对飞机飞行条件变化引起的模型不确定性问题,基于μ控制理论设计鲁棒的俯仰姿态控制系统。首先,根据干扰抑制原理将俯仰姿态控制系统设计转化为μ综合的一般框架,合理地选择加权函数确定广义被控对象,通过引入虚拟的不确定块将鲁棒性能问题转化为广义系统的鲁棒稳定性问题。然后,利用D-K迭代算法求解得到14阶的μ控制器,基于平衡截断方法将该控制器成功地降为4阶。最后对μ降阶控制器进行了鲁棒性分析,并与在相同加权函数条件下设计的H∞控制器相比较,结果表明μ控制兼顾了系统的鲁棒稳定性和鲁棒性能,避免了保守性。

Abstract:

Aiming at the problem of model uncertainty caused by the change of flight conditions, robust pitch attitude control system was designed using μ control theory. Firstly, the pitch attitude control system design was constructed into the general framework of μ synthesis according to the principle of interference suppression. And weighting functions was selected properly to get the augmented controlled object. Then by introducing fictive uncertainty, the robust performance problem was transformed into robust stability problem of augmented system. Secondly, the D-K iteration algorithm was used to solve the fourteenth-order controller. And this controller was reduced to fourth-order successfully using the balanced truncation model reduction procedure. Lastly, robustness analysis was performed in terms of the reduced-order μ controller. Compared with H∞ controller designed using the same weighting functions, the reduced-order μ controller yields the desired robust stability as well as the robust performance avoiding conservativeness.