Novel Three-Phase AC-AC Z-Source Converters Using Matrix Converter Theory

This paper proposes a new type of three-phase AC-AC Z-Source converters which are derived from matrix converter (MC) theories. The proposed converters are capable of three-phase AC-AC power conversion and, except for exhibiting the input characteristics of MC: controllable (unity, leading and lagging) input power factor, it does overcome the two main drawbacks of MC: limited voltage transfer ratio and low immunity to grid disturbance by utilizing a Z-Source network. The complete modulation strategy of the proposed converter is developed from Z-Source modulation and space vector modulation (SVM) of MC. And thereby important aspects of the developed AC-AC converter, i.e., switching operation and realization, are presented together with theoretical analysis, which gives an in-depth understanding of the proposed converters. Finally, the MC concept based Z-Source topology is verified by numerical simulation and experimentally using a laboratory prototype.