A Space Vector Modulated Quasi-Z-Source Based Four-Level VSI for PV Application

A Four-level Inverter system is presented in this paper, which employs a Space Vector Modulated Quasi-Z-Source to obtain high-boost inversion for PV applications. Unlike the conventional Multilevel Inverters, such as Neutral-Point Clamped (NPC) and the Cascaded H-Bridge (CHB) configurations, the proposed inverter uses only 19 power semiconductor switching devices and three Quasi-Impedance networks. It is also shown that by employing level-shifted carrier modulation, one can achieve higher shoot through duty ratio, enhancing the boosting capability of the proposed inverter. The performance of the proposed power circuit is assessed with simulation studies, which reveal its applicability for PV applications.