Reducing chattering phenomenon in sliding mode control of Buck-Boost power converters

This paper focuses on the problem of controlling DC-to-DC switched power converter of Buck-Boost type. The converter is controlled according to pulse-width-modulation (PWM) and is modeled by an average nonlinear state-space representation. A nonlinear regulator is designed using the sliding mode technique. The control purpose is to enforce the output voltage to track any desired reference signal and to prevent chattering phenomenon which is, usually, caused by the excitation of fast unmodelled dynamics. The obtained regulator is shown to meet its objective.