Three‐phase common‐ground‐type photovoltaic inverter without shoot‐through problem

Abstract

SummarySince there are common mode leakage current (CMLC) and shoot‐through problems in the conventional three‐phase transformerless photovoltaic (PV) inverters, the three‐phase common‐ground‐type transformerless dual‐buck inverters (DBIs) are derived. By shorting the neutral point of the three‐phase load and the negative terminal of the PV panel, the CMLC is eliminated. The DBIs has no shoot‐through problem and there is no current flowing through the body diode of the SiC metal oxide semiconductor field‐effect transistor (MOSFET). The three‐phase DBI combined with a buck‐boost converter is taken as an example to illustrate the operating principle of the derived inverters. The control strategy of the inverter is given. A prototype is built to validate the proposed inverter. Finally, comparison among the proposed inverter and other three‐phase inverters is given.