Comparative analysis of three phase ac-ac Z-source converter topologies

Impedance (Z) source converters have been evolved as a new type of converter in addition to the two other existing converters; voltage source and current source converters. The new converter has many inherent advantages which can be used for many applications such as wind power conversion system, fuel cell and motor drive applications. Current research works focuses mainly on using Z-source network as a dc-link. The three phase ac-ac Z-source converter (TPZC) buck boost capabilities are verified to perform ac-ac conversion directly. Two different topologies of TPZC are compared in this paper. The boost ratio of improved topology is nearly 1.8 which is higher than 1.15 of traditional topology. Mathematical analysis of the proposed converters verified by MATLAB simulation results is presented.