Design of initial conditions based sliding mode controller for buck converter

This investigation is to design an optimal pulse width modulation form of sliding mode controller for buck converter. In this controller design, the converter parameters and the initial conditions of the state variables are made use of. The Proportional Integral Derivative type of switching surface is chosen and continuous current conduction mode of operation is assumed. The design method is illustrated by considering an already existing example in the literature. The switching coefficients obtained proved to be yielding a robust switching surface both for load and line variations. It is shown for the first time that the initial conditions based sliding mode controller is having satisfactory line robustness and excellent load robustness. It still ensures much reduced control effort for maintaining sliding mode motion under wide variations.