Abstract

In recent years, predictive control has emerged as an alternative for the control of power electronic converters. In this paper, a comparison is presented between the implementation of a predictive current control strategy operating at variable switching frequency and another working at fixed switching frequency. Both strategies use a mathematical model of the converter and load in discrete time in order to predict the behaviour of the load currents and thus choose the switching state that minimizes a given cost function, state which is applied in the next sampling time. The comparison is done based on the percentage of total harmonic distortion (THD) and the error of the output current compared to its reference. The results demonstrate that both techniques work well, but the one operating a fixed switching frequency generates lower ripple and harmonic distortion.