Comparison of PID Controller with a Sliding Mode Controller for a Coupled Tank System

-Controlling the level of the liquids is a critical need in many industrial processes. Often the tanks are so coupled together that the levels interact and exhibits a nonlinear behavior. The sliding mode control (SMC) is used to control the level of the coupled tank system. Initially we develop the mathematical model for a non-linear single-input singleoutput (SISO). A simulation is carried out using MATLAB/SIMULINK to control the non-linear model of coupled-tank system. The step input signals is fed to the system to test the tracking performance of SMC. The tracking performance of SMC is also compared with conventional PID controller in terms of performance index ITAE. The SMC showed excellent tracking results than PID controller.