Fractional order PIλ control strategy for a Liquid Level System

This paper deals with the design of fractional order proportional integral (PI
^λ
) controller for Liquid Level System (LLS). To achieve this, a fractional order model of LLS (FO-LLS) is obtained using J-index optimization method. Based on this model, a fractional order PI
^λ
controller satisfying required gain margin (GM) and phase margin (PM) using Stability Boundary Locus method is designed. Simulation of LLS control system is carried out for the set point tracking. Performance of the PI
^λ
controller designed by FO-LLS model is compared to that of Chidambaram's integer order PI controller for integer order model. Finally, the robustness of both control systems is considered.