基于非光滑观测器的带死区三明治系统状态估计

在控制工程实际中，许多含有死区的系统可以用带死区的三明治系统描述．本文针对带死区的三明治系统特点，构建了一种非光滑观测器以对系统状态进行估计．首先根据带死区三明治系统的特点，由分离原理，建立了描述系统特性的非光滑状态空间方程．据此构造了能够随系统工作区间变化而自动切换的非光滑观测器，给出了相应的收敛定理及其证明．最后通过仿真，分别比较了非光滑观测器和传统的观测器对状态的跟踪效果，比较结果表明非光滑观测器对于带死区三明治系统状态变量估计的准确性要优于传统的观测器．

Non-smooth observer for sandwich systems with dead-zone

In control engineering practice, many systems involving dead-zone can be described by the so-called sandwich systems with dead-zone. In this paper, a novel non-smooth observer is proposed to handle the state estimation for the sandwich systems with dead-zone. Based on the characteristics of the system, a non-smooth state-space equation is constructed by the separation principle; and then, a non-smooth observer is developed based on this state-space equation. The observer can be switched among different operating zones automatically according to the change of operation conditions. The convergence theorem of the non-smooth observer and its proof are given respectively. Simulations are performed. The comparison of simulation results between the proposed non-smooth scheme and the conventional method is illustrated. It shows that the proposed non-smooth approach is much better than the conventional one in estimation performances.