Control and Application of Grid-Connected Cascaded H-Bridge PV Inverters

Abstract

In the case of grid-tied PV inverters, in general terms, the quality of current remains the determinant of the power quality, as voltage of a PV inverter cannot be controlled. Therefore, the current control strategy carries a prime importance for a grid-tied system. Low levels of harmonic distortion, increased dynamic response, and the DC-link voltage regulation are the fundamentals requirements that must be satisfied by a grid-tied system. Here, the entire output produced by the PV systems largely depends on the current-control technique employed. This paper offers an overview of various current control schemes and presents a novel current control technique for grid-connected cascaded H-bridge PV inverters. This control technique is implemented on a π (Pi) type thriteen level cascaded H-bridge (PiCHB) PV inverter.