An expert system based soft Computing control technique for a First order plus dead time nonlinear Process

Abstract

In this work an attempt has been made to develop a suitable control newlinescheme for the First Order Plus Dead Time FOPDT heat exchanger model newlineunder various operating conditions The precision control of temperature is newlinedifficult due to the presence of nonlinearity timing of the varying operating newlineconditions, and the time lag The mathematical model of a heat exchanger newlinesystem is identified as a FOPDT model using the Process Reaction Curve newline PRC method newlineControllers are grouped into four classes viz conventional controllers newlineintelligent controllers heuristic algorithm tuned PID controllers and advanced newlinecontrollers Their performance analysis is carried out, based on time domain newlinespecifications Rise Time Peak Time Settling Time and Peak Overshoot newlineand error performance indices ISE and IAE newlineFirst the performance analyses of conventional controllers such as newlineFeedback Controller FBC Feedforward Feedback Controller FF FBC and newlineSet Point Weighted Controller SPWC are examined under servo and newlineregulatory operations which provide control guidelines for the FOPDT heat newlineexchanger process It is observed that any large shift in the operating point newlinewithout changing the controller tuning parameter leads to larger oscillations newlineand longer settling times newline newline