Smith-predictor based enhanced Dual-DOF fractional order control for integrating type CSTRs

Abstract Continuously Stirred Tank Reactors (CSTR) are one of the widely used reactors in the chemical industry. Controlling such reactors is challenging because many times it demonstrates a model which is having a pole at the origin of the s-plane. Moreover, the presence of a dead time necessitates more effective control measures. This work presents a modified smith predictor-based control for integrating type CSTRs with time delay in order to provide adequate servo and regulatory closed-loop responses. Numerous researches on dual DOF control suggested different controller settings for outer and inner-loop controllers. But, in the current study, both the controllers are proposed to be the same which drastically reduces the complexity of the design. To offer good robustness in the closed-loop response, the controller is synthesized with a user-defined maximum sensitivity. Case studies on CSTRs for both the nominal and disturbed process models are conducted and the same is compared with recently developed control laws. Lastly, a performance comparison on ISE, ITAE, and IAE is provided.