Title :
Discrete Variable Structure Control Design and Its Application to a Ship Autopilot Servo System
Author :
Song, Lizhong ; Yao, Qionghui ; Yan, Shengmao
Author_Institution :
Coll. of Electr. & Inf. Eng., Naval Univ. of Eng., Hubei
Abstract :
This paper presents a new approach to the discrete-time variable structure control design. Firstly, a new discrete reaching law, which is stable at the origin and can eliminate the chattering caused by conventional discrete reaching law parameters, is proposed. Subsequently, an algorithm for uncertainty estimation is developed. It can be shown that the estimation error dynamics can be decoupled from sliding surface dynamics using the proposed scheme. Robust stability of the closed-loop system can be ensured in the presence of uncertainties with bounded changing rate. No chattering occurs. The proposed algorithm is applied to the control of a ship autopilot servo system. Simulation results show that the proposed controller can track a desired course well whether uncertainties are present or not
Keywords :
closed loop systems; discrete time systems; robust control; servomechanisms; ships; uncertain systems; variable structure systems; closed-loop system; discrete reaching law; discrete-time variable structure control; error dynamics estimation; robust stability; ship autopilot servo system; sliding surface dynamics; uncertainty estimation; Control design; Control systems; Design engineering; Differential equations; Estimation error; Marine vehicles; Robust stability; Servomechanisms; Sliding mode control; Uncertainty; discrete variable structure control; ship autopilot; sliding mode control;
Conference_Titel :
Electrical Machines and Systems, 2005. ICEMS 2005. Proceedings of the Eighth International Conference on
Conference_Location :
Nanjing
Print_ISBN :
7-5062-7407-8
DOI :
10.1109/ICEMS.2005.202826
