Design and Analysis of Sigma Z-Source Inverter for PV Applications 2019-28-0123
Traditional Voltage Source Inverter (VSI) produces lesser output voltage than the input and cause shoot-through due to the gating of the semiconductor device connected in same leg. These inadequacies can be overcome by Z-source inverter (ZSI). The ZSI has been extensively used in applications such as electric drives, PV system and uninterrupted power supply. Nevertheless, the conventional ZSI grieves from limitations such as restricted boost capability, discontinuous input current and high inrush current. An alternative for this limitation is to use a transformer replacing inductors in the impedance source network. In high-voltage gain applications, the single transformer-based ZSI topologies requires more turns ratio resulting in large transformer windings. For improving the boost capability, the T-ZSI uses two transformers in the Z-source network and this permits lower turns ratio transformer to be used. Similar to the single transformer-based ZSI topologies, the turn ratio of the T-ZSI is raised to increase the voltage gain. In this paper, an alternative topology of T-ZSI that incapacitates the shortcomings of having high turns ratio to increase the boost capability is investigated. The sigma-ZSI is realized by changing the secondary transformers’ windings to be in series with the capacitors. Consequently, its boost capability can be increased by reducing the turns ratio of the transformers and the performance analysis of sigma-ZSI is discussed in this paper.
Kalaiarasi Nallathambi, Uthra Rangarajan, Anitha Daniel
SRM Institute Of Science And Technology
International Conference on Advances in Design, Materials, Manufacturing and Surface Engineering for Mobility