Current-Fed Soft-Switching Push-Pull Front-End Converter-Based Bidirectional Inverter for Residential Photovoltaic Power System

Photovoltaic (PV) residential power system is an important application of renewable energy. The parallel-connected configuration of PV modules rather than the series-connected configuration become popular considering the safety requirements and making full use of the PV generated power for the PV residential generation system. In this paper, a novel soft-switching current-fed push-pull front-end converter-based inverter is proposed. Push-pull converter has only two primary devices with common ground to supply and results in simple and reduced gating requirement. The device voltage is clamped naturally by secondary modulation without active clamping circuit or passive snubbers. Zero-current switching of primary devices and zero-voltage switching of secondary devices is achieved. Soft-switching is inherent owing to proposed secondary modulation, load independent, and is maintained during wide variation of input voltage and power transfer capacity, and thus is suitable for PV applications. A 250-W laboratory prototype of the converter is built and tested to demonstrate the converter performance over wide variations in input voltage and output power for PV applications.