Filtered smith predictor applied to a boost converter for minimizing the effect of non-minimal phase and rejection of disturbances

Abstract

The boost converter is a dc-dc power converter which is able to raise the input voltage level to the output load, according to the duty cycle. It is a well-known power converter used in several applications, i.e. power supplies, LED's applications, uninterrupted power system, converters for renewable energies, among others. However, the boost converter small-signal model is a non-minimal phase system, which usually has a undershoot response, a steady-state error, and a slow transient response due to the zero in the right half-plane. Therefore, this paper shows a control technique based on the Filtered Smith Predictor, in order to mitigate the non-minimal phase effect, eliminate the complex poles with low damping factor, increase the relative stability and increase the system's time response. The simulation and experimental results will be presented and discussed. Furthermore, the results will be compared with the conventional PI controller.