Design and implementation of nonlinear Control schemes on the simulated model Of CSTR and PH processes

Abstract

PID controller and linear model predictive controller are the two newlinemost popular control schemes that have been widely implemented throughout newlinethe chemical process industries for the past three decades However control newlineof nonlinear systems using the above linear control schemes does not give newlinesatisfactory performance at all operating points the reason being that the newlineprocess parameters of the nonlinear process will vary with the operating newlineconditions Moreover the PID controller tuned at one operating condition newlinemay not provide satisfactory servo and regulatory performances at shifted newlineoperating points It should be noted that to achieve improved closed loop newlineperformance a different set of controller settings for each operating condition newlinehas to be used In the case of model based control schemes the accuracy of newlinethe model will have significant effect on the closed loop performance of the newlinecontrol system newlineIn this thesis two nonlinear systems CSTR and pH Process newlineconsidered for simulation study have been represented as family of local newlinelinear models Local PID controllers and Local internal model controllers newline IMC have been designed on the basis of local linear models and the newlineweighted sum of the output from either local PID controllers Nonlinear PID newlineController or the local IMC controllers Nonlinear IMC has been used to newlinecontrol the nonlinear systems CSTR and pH Processes newline newline