Single-phase common-grounded transformerless grid-tied inverter for PV application

Abstract

In this study, a novel topology for the single-phase transformerless grid-connected inverters family is proposed. By using the series-parallel switching conversion of the integrated switched-capacitor module in a packed unit, several merits can be added to the proposed inverter, such as higher efficiency, boosting ability within a single-stage operation, and removing the leakage current problem by using the common grounding technique. In this study, a peak current controller strategy is implemented in order to generate the gate pulses of semiconductor switches. Moreover, this strategy is used to control both the active and reactive powers. Therefore, a thoroughly controlled current with a proper quality can be supplied to the grid from a single source renewable energy resource. The operating procedure, design consideration, comparison study, and the experimental results for a 510 W prototype are presented in order to validate the correctness and feasibility of the proposed topology.