Optimized PI controller for an interacting spherical tank system

This paper presents liquid level control of interacting spherical tank system using PI controller. The spherical tank is divided into four regions and for each region a particular PI controller is designed. Initially the parameters are tuned using the conventional tuning formulae of Ziegler-Nichols. Although conventional tuning formula gives a good stating solution but it lacks in obtaining all the design requirements. Thus the PI controller is optimized by grey wolf optimizer to enhance the system performance and to achieve the desired time-domain requirements. The results are validated by calculating the performance indices like integral square error. Simulation results validate effectiveness of the proposed scheme as compare to the literature.