Design of Some Chatter free Sliding Mode Controllers for Process Control Applications

Abstract

In industrial process control, the design and tuning of controllers are more difficult. The newlinePID controller is themost popular in process industries because of its outstanding efficacy newlineand simplicity in implementation. But, the processes having time delay and non-linear newlinebehaviour in addition to known and/or unknown uncertainty and disturbances are dif- newlineficult to control with such type of conventional controllers. Hence robust controllers are newlinemore proper choice to handle with such type of problem. Sliding Mode Control (SMC) newlineis the robust controller which is insensitive to parametric uncertainty and disturbances. newlineHowever, SMC has unwanted complement known as chattering due to discontinuous newlineterm in the control law which may be harmful to actuators. Also it can stimulate un- newlinemodeled high frequency dynamics of the system. Uncertainty and disturbance estimator newlineis one of robust controlmethods which estimates the unknown dynamics, unknown mea- newlinesurable disturbances and provides chatter free control. The main objective of the work newlinepresented in this thesis, is to study and design some chatter free sliding mode controller newlinestrategies for process control applications by ensuring the stability and enhancing the newlineperformance of SISO and interacting MIMO processes. newlineIn this thesis chatter free sliding mode control algorithms are designed and applied newlinefor process control applications. Some advanced sliding mode control maintains the newlinemain advantages of standard sliding modes and has the additional advantage that it can newlinebe used to remove chattering effect and hence, provide smooth control. The proposed newlinemethods are also improved the performance than conventional sliding mode control. newlineIn this thesis, second order sliding mode controller (SOSMC), dynamic sliding mode newlinecontroller (DSMC), fast terminal sliding mode controller (FTSMC) and extended state newlineobserver based sliding mode controller (ESO-SMC) design approaches are presented for newlineprocesses control. In all the mentioned approaches some approaches are designed for newlinemultiple-input multiple