Sliding Mode Control for Nonlinear Discrete Networked Cascade Control Systems With Uncertain Delay

In this paper, the problems of modeling and sliding mode control for a class of nonlinear discrete networked cascade control systems (NCCSs) are studied. Firstly, a class of discrete networked cascade control systems with nonlinear disturbance is considered, the sliding mode control is introduced and the model of the system is established. Based on this model and the Lyapunov functional method, the state feedback primary controller and the sliding mode secondary controller for this system are co-designed. Finally, an example of a thermal power plant is given to illustrate the effectiveness of the proposed co-design method. The main advantages are that the sliding mode control is introduced into cascade control system (CCS) and the design method of sliding mode controller for this system is proposed for the first time. On the premise of ensuring the stability of the system, it can be driven to the sliding mode surface in a limited time, and remain on the sliding mode surface in all subsequent times. The method can achieve better results and be applied to the corresponding industrial system with networked cascade control structure.