具有执行器饱和的不确定系统的干扰抑制控制

Disturbance rejection control for uncertain systems with actuator saturation

针对传统的干扰观测器(DO)设计并未考虑实际系统中普遍存在的执行器饱和问题,提出了一种具有抗饱和补偿的基于干扰观测器的控制(DOBC)策略.首先探究传统DOBC在执行器饱和时产生积分饱和现象的原因;然后通过最小化性能指标设计了一种抗积分饱和的补偿器,并将其与DO结合,使得修改后的DOBC能够有效处理执行器饱和;最后对所得闭环系统进行局部渐近稳定性分析.比较仿真结果表明,存在执行器饱和时,所提出控制方法具有更小的位置跟踪误差和干扰估计误差,并且设计的补偿器可以保持DO的状态尽可能接近没有执行器饱和时的状态,进而验证了所提出控制方法在抗干扰和抗饱和方面具有优越性.

To address the issue that conventional disturbance observer(DO)design did not consider actuator saturation,which is prevalent in practical systems,a DO-based control(DOBC)strategy with anti-windup compensation is proposed.First,the reason of windup phenomenon in the conventional DOBC when the actuator is saturated is studied.Then,an anti-windup compensator is designed by minimizing the performance index,and patched to the DO so that the modified DOBC can effectively handle actuator saturation.Finally,local asymptotic stability analysis is performed on the resulting closed-loop systems.Comparative simulation results show that when there is actuator saturation,the proposed method has smaller errors in position tracking and disturbance estimation,and the designed compensator can maintain the DO states to be as close as possible to those without actuator saturation.This verifies that the proposed method is superior in anti-disturbance and anti-windup.