Design of Integral Sliding Mode Controller for Nonlinear MIMO System

Abstract

In this project, the controller is designed and simulated using sliding mode controller with integrator for uncertain nonlinear Multi Input Multi Output (MIMO) three tank system. Robustness against unknown disturbances are considered and improved using SMC with integrator. A sliding mode controller is a robust controller against the external disturbance. Consequently, robustness against uncertainties increases from the very beginning of the process. Furthermore, the control laws considerably alleviate chattering along the switching manifold. In addition, the performance of the controller boost up in the presence of uncertainties. An ideal sliding mode controller has a discontinuous switching function like saturation, hyperbolic, signum and tangent. Such a switching functions produce a chattering phenomenon that is highly undesirable. This chattering phenomenon is reduced by integral sliding mode controller. For the above mention reason, the robust controller is designed for MIMO nonlinear three tank system. A comprehensive comparative analysis carried out with sliding mode control and integral sliding mode control which demonstrates superiority of the newly designed control law. A reduced chattering regulate uncertain nonlinear system with improved performance in the presence of external disturbances, which ensures the robustness of the proposed integral sliding mode controller.