扩张状态观测器下的自适应输出反馈控制

Adaptive Output Feedback Control Based on Extended State Observer

针对一类不确定非线性系统,研究了一种结合反步法和自抗扰控制的新的自适应输出反馈控制方法。通过引入扩张状态观测器(ESO)对被控系统的未知状态进行实时估计,同时利用扩张状态观测器实现对系统中的不确定项在线逼近及补偿。通过非线性滤波器对反步法设计过程中的虚拟控制信号进行求导,避免了传统反步法设计控制中复杂性爆炸的问题,并由此设计了自适应输出反馈控制器。通过李雅普诺夫函数证明了这种控制方法的稳定性,验证了闭环系统中所有信号均是有界的。数值仿真算例进一步验证了该方法的有效性。

For a class of uncertain nonlinear systems a new adaptive output feedback control method combining backstepping with active disturbance rejection control is investigated.By introducing the Extended State Observer(ESO)the unknown state of the controlled system is estimated in real time.At the same time the ESO is used to implement online approximation and compensation of the uncertain terms in the system.The nonlinear filter is used to differentiate the virtual control signal during the backstepping design process which avoids the complexity explosion problem in the traditional backstepping design control and an adaptive output feedback controller is designed accordingly.The stability of this control method is proved by Lyapunov function and it is verified that all signals in the closed-loop system are bounded.Numerical simulation examples further verify the effectiveness of the method.