One-cycle control of a delta-connected cascade H bridge rectifier

One cycle PFC technique has advantages of AC voltage sensor elimination and simplified current loop, thus it has been utilized on various rectifier topologies. In this paper, a modified one cycle PFC method for the delta-connected cascade H bridge (CHB) rectifier is proposed, which combines the one cycle PFC control, zero sequence current injection control and DC voltage balancing control. With the proposed method, unity power factor, unbalanced phase load compensation and DC voltage balance are achieved without using AC side voltage sensors. The validity of the proposed method is verified by both switching model simulation and experiment results.