Non-smooth observer for sandwich systems with dead-zone
基于非光滑观测器的带死区三明治系统状态估计

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.