Non-linear design of dc-dc buck converter to assess the performance under steady state and dynamic operation

Buck converters are widely used in switch mode power supplies due to their high efficiency, fast switching actions, low volume and weight, and low cost. These converters are variable structure systems and contain nonlinearities which lead to oscillations during operation. Various Control techniques have been investigated and analyzed in order to minimize oscillations during the operation of the converter, in particular, under non-linear situations. In this paper, an attempt is being made to control the oscillation of the buck converter by using sliding mode controller. The SMC (Sliding Mode Controller) is a nonlinear controller which can handle nonlinearities, provides good dynamic response and simple implementation. The proposed control scheme is implemented and simulated in MATLAB/Simulink. The results of SMC are compared with cascade controller and are presented in this paper. (author)