A low frequency predictive current control for multilevel active rectifiers

In this paper a new low frequency predictive current control is proposed for a single phase cascaded H-bridge multilevel rectifier. The control method has been fully investigated with theoretical analysis, simulation and experiments on a laboratory prototype with five series-connected H-bridges. However the analysis and technique is valid for any general N-level structure. The simulations and experimental results presented demonstrate the excellent performance of the predictive control in terms of ac current waveform quality, power factor and reduced switching frequency of each bridge in comparison to traditional PI based control schemes.