AN IMPLEMENTATION OF COMPENSATION SCHEME OF TIME DELAY WITH NETWORK CONTROLLED SYSTEM APPLICATION

Abstract

Feedback control systems wherein the control loops are closed through a real time network are called networked control system (NCSs). Network control systems (NCSs) are spatially distributed systems in which the communication between sensors, actuators, and controllers occurs through a shared band limited digital communication network. Time delay occurs used for networked control system when the exchange of data among sensors, actuators and controllers connected through the shared medium. Such delays affect the system Performance degradation and the reduced stability or total instability of the closed-loop system. To study in reality an experimental work is done to transfer packet data between two computer systems through a Local area Network (LAN) using UDP protocol. Subsequently the transfer of signal between two computer systems through a LAN using UDP protocol has been also made. These experiments were carried out using SIMULINK Instrument Control Toolbox (ver7.6). Networked predictive control is also designed for networked control of servo system. This control strategy is applied to a servo control system through the Local Area Network (LAN).SMITH-PREDICTOR proposed to compensate the communication delays in the networked control system