Adaptive sliding mode control of PWM boost DC-DC converters

The problem of controlling switched boost power converters, in presence of load uncertainties, is considered. The converter is controlled according to pulse-width-modulation (PWM) and is modeled by an average nonlinear state-space representation. The control purpose is to enforce the output voltage to track any desired reference signal. First, supposing the converter model to be fully known, a nonlinear regulator is designed using the sliding mode technique. Accordingly, the control objective is reformulated in term of a sliding surface. The obtained regulator is shown to meet its objective and proves to be robust with respect to small load uncertainties. To deal with large uncertainties, an adaptive regulator is designed using the same technique. The adaptive regulator also meets its objective. Furthermore, its performances turn out to be less sensitive to the values of the associated design parameters.