广义非线性扩张状态观测器设计及性能分析

针对时变外扰,提出广义非线性扩张状态观测器设计方法.在分析传统扩张状态观测器的设计策略的基础上,通过对总扰动进行重构、引入广义扩张状态,设计反映扰动中已知分量的广义扩张状态观测器(扩张r+1阶).理论分析了观测器的收敛性,并得出了观测误差上界与扩张阶数的定量关系式.通过仿真对广义扩张状态观测器抑制外界正弦扰动的有效性进行检验,数值模拟结果表明,本文设计的观测器能够有效利用扰动中已知分量的信息,降低系统的不确定性,提高观测精度.

Design and performance analysis of generalized nonlinear extended state observer

A generalized nonlinear extended state observer design method is proposed for time-varying disturbances. Based on the analysis of the system reconstruction strategy of the traditional extended state observer, the generalized extended state observer reflecting the known components of the disturbance is designed by reconstructing the total disturbance and introducing the generalized extended state. The convergence of the observer is analyzed and the quantitative relation between the upper bound of the observation error and the expansion order is obtained. The effectiveness of the generalized extended state observer to suppress the external sinusoidal disturbance is verified by numerical simulation which further shows that the observer can utilize the known components of the disturbance, reduce the uncertainty of the system and improve the observation accuracy.