Naturally commutated and clamped soft-switching current-fed push-pull voltage doubler based solar PV inverter

The photovoltaic (PV) residential power system is an important application of renewable energy. 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 (ZCS) or natural commutation of primary devices and zero-voltage switching (ZVS) 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 is built and tested to demonstrate the converter performance over wide variations in input voltage and output power for PV applications.