Discrete-Time Sliding Mode Based Controller of DC-DC Buck Converter
This paper presents the control of DC-DC buck converter. The control strategy is based on the theory of discrete-time sliding mode control to ensure robustness against parameter variations and external disturbances. The output voltage regulation is achieved using a digital controller that combines discrete-time first-order sliding mode control with a discrete-time realization of the super-twisting algorithm, commonly used in second-order sliding mode control. The design of the proposed controller is performed using a discrete-time model of the DC-DC buck converter. Extensive simulations were conducted in Matlab/Simulink to validate the performance of the control algorithm under varying load conditions and input voltage fluctuations. A comparative study between conventional PI controller and the proposed discrete-sliding mode based controller in tracking of various voltage references under action of disturbances is given.