高超声速飞行器非线性鲁棒控制律设计

高超声速飞行器具有模型非线性程度高、耦合程度强、参数不确定性大、抗干扰能力弱等特点,其自主控制具有较大的挑战.论文提出了一种基于鲁棒补偿技术和反馈线性化方法的非线性鲁棒控制方法.文中首先采用反馈线性化的方法对纵向模型进行输入输出线性化,实现速度和高度通道的解耦和非线性模型的线性化.针对得到的线性模型,设计包括标称控制器和鲁棒补偿器的线性控制器.基于极点配置原理,设计标称控制器使标称线性系统具有期望的输入输出特性,利用鲁棒补偿器来抑制参数不确定性和外界扰动对于闭环控制系统的影响.基于小增益定理,证明了闭环控制系统的鲁棒稳定性和鲁棒跟踪性能.相比于非线性回路成形控制方法,仿真结果表明了所设计非线性鲁棒控制算法的有效性和优越性.

Nonlinear robust controller design for hypersonic vehicles

Hypersonic vehicles are characterized by high model nonlinearity, strong coupling, large parameter uncertainties, and low disturbance rejection, which pose a challenge for their automatic controller design. We propose a nonlinear robust control method based on the robust compensation technique and feedback linearization method. The feedback linearization method is firstly applied to achieve the output/input linearization for the longitudinal model, resulting in a linear model. Then, a linear robust controller consisting of a nominal controller and a robust compensator is designed for the obtained linear model. The nominal controller is designed based on the pole assignment algorithm to guarantee the outputs of the nominal linear closed-loop system to track the desired references, while the robust compensator is introduced to restrain the effects of parametric uncertainties and external disturbances on the closed-loop control system. Based on the small gain theorem, the robust stability and the robust tracking properties are proved. Numerical simulation is implemented to validate the higher effectiveness and more advantages of the proposed nonlinear control method over the nonlinear loop-shaping control method.