具有输入约束和输出噪声的不确定系统级联线性自抗扰控制EI北大核心CSCD

针对一类具有输入约束和输出噪声的SISO(Single input single output)不确定非线性系统,提出了一种基于误差补偿和工程滤波的抗饱和级联线性自抗扰控制(Linear active disturbance rejection control,LADRC)方法.首先针对高频量测噪声,分析了线性扩张状态观测器(Linear extended state observer,LESO)对噪声的放大机理及其与观测器增益的定量关系,进而设计了一种基于工程滤波器的级联LADRC方法,在滤除噪声的同时有效补偿了因滤波所造成的输出幅值和相位损失,确保了闭环系统的跟踪精度.然后继续考虑输入饱和的问题,利用LADRC的实时估计/补偿能力,通过将饱和差值信号引入LESO,设计了一种基于误差补偿的抗饱和LADRC方法,有效减小了系统设计控制量,避免了系统长时间陷入饱和.通过实时仿真比较,验证了所提出方法的有效性.

Cascaded Linear Active Disturbance Rejection Control for Uncertain Systems With Input Constraint and Output Noise

For a class of SISO (single input single output) uncertain nonlinear systems with input constraint and output noise, an anti-saturation cascaded linear active disturbance rejection control (LADRC) method based on error compensation and engineering filtering is proposed. Firstly, aiming at high frequency measurement noise, the amplification mechanism of linear extended state observer (LESO) and its quantitative relationship with LESO gain are analyzed. On this basis, a cascaded LADRC scheme using engineering filter is designed to remove the noise while compensating for the amplitude and phase losses of system output caused by filtering, which ensures the tracking accuracy of closed-loop system. Then continuing to consider input saturation, using the real-time estimation/compensation capability of LADRC, the saturation difference signal is introduced into LESO, thus an anti-saturation LADRC scheme based on error compensation is designed, which effectively reduces the designed control variable and avoids the system falling into saturation for a long time. By real-time simulation comparison, the effectiveness of the proposed method is verified.