A Robust Stability Region-Based Decentralized PI Controller for a Multivariable Liquid Level System

The article presents a design and development of a new robust decentralized PI controller based on a robust stability region for a multivariable system. We determine the stability boundary region of the PID controller parameters that satisfy the ${{H}_{\infty }}$ sensitivity criterion. In this article, multiplicative input and output uncertainties have been considered to illustrate robust stability. Moreover, to verify the robust performance of the proposed controller, a comprehensive comparative analysis is made between the proposed controller with another decentralized controller. Simulation results justify the efficacy of the proposed robust decentralized controller. The obtained responses confirm that the proposed robust decentralized controller exhibits better set point and disturbance attenuation performance as compared to other decentralized controllers.