A novel modulation technique for a multilevel hybrid converter with floating capacitors

This paper presents a novel modulation technique for a multilevel hybrid converter. This technique is based on a finite state machine which decodes the comparison between the reference signal and four level shifted carriers arranged in phase. The objective of this state machine is to achieve a appropriate alternation between redundant states in order to naturally balance the converter floating capacitors. A description of the considered hybrid topology and detailed explanation of the proposed modulation method are presented. The benefits of the integration between both, hybrid converter and proposed modulation, are also discussed. In particular, modulation performance using relatively low frequency carriers is studied to find a good trade-off between current waveform quality and converter switching losses. Simulation analysis and results of the operation of this converter as active front rectifier are presented using 1[kHz] carrier frequency.