Design and Implementation of Dual-Frequency Single-Phase Grid-connected Inverter

In order to improve the quality of the output current and reduce power losses of the grid-connected inverter, a novel parallel dual-frequency single-phase grid-connected inverter is proposed. The low-frequency unit operates at the lower switching frequency to reduce the switching losses, and the high-frequency unit operates at the higher switching frequency to suppress the harmonic current. The main circuit of the inverter is the low-frequency inverter unit, and the high-frequency unit operates in the rectification state as the auxiliary module. This dual-frequency mode reduces switching losses, improves system efficiency, and guarantees the quality of the grid-connected current. This paper introduces the Design and implementation methods of the inverter, as well as the experimental results of the prototype.