Control of Variable Time Delay Processes

Abstract

Significant time delay or dead time comprises processes in their responses. The dead time defined as time elapsed between the instant processes a deviation occurs and when the first improving action is taken. The Performance of control system has profound effect from the dad time. Dead-time processes in industry are very common and controller design is also been shown for the systems exhibiting .The difficulties of estimating the dead time and phase lag dead time greatest difficulty in design. Process with Variable dead time is difficult to control with the simple and basic smith predictor, as it is used only in constant time delay processes. To overcome the problem of variable time delay different, methods is been introduced with the help of Simulink in MATLAB and comparisons of them. There are also many methods which are physically used in the electronic circuitry. The Physical implementation of variable time delay will also be useful in many practical aspects. Another major part of the report focuses on improving the controller performance by solving the variable delay time problem using IMC. An IMC structure was proposed for unstable processes with time delays and processes. A design method aiming at system robustness was proposed for the advantage of the structure. The variable time delays creating problems in the system is been analysed in the various methods.