A discrete repetitive adaptive sliding mode control for DC-DC buck converter

The problem of sensitivity to uncertainties and disturbances is still a challenging task in the theory of discrete sliding mode controller. In this article, a discrete repetitive adaptive sliding mode control using only input-output measurements of linear time-varying system with periodic disturbances is proposed. A new indirect adaptive algorithm taken into account the periodicity of disturbances is used to identify parameter variations of the considered system. Based on this identification, discrete sliding mode controller is developed. Then, the structure of plug-in repetitive control is integrated into the previous controller to reject harmonic disturbances. A robustness analysis is achieved to ensure the asymptotic stability of the proposed controller. An example of time-varying DC-DC buck converter subject to harmonic disturbances is carried out to illustrate the effectiveness of the designed discrete repetitive adaptive sliding mode control.