Single-Stage Single-Phase Isolated Full-Bridge Buck–Boost DC–AC Inverters

This article presents a simple high-frequency transformer (HFT) isolated buck–boost inverter designed for single-phase applications. The proposed HFT isolated inverter, with its full-bridge buck–boost topology, provides a wider voltage regulation range. It can efficiently step up or step down the input voltage to achieve the desired output ac voltage. It provides galvanic isolation between the input and output sides. This feature ensures safety and compatibility with applications that require isolation, such as renewable energy systems and electric vehicle charging. It utilizes a solitary output inductor, an HFT for isolation, and ensures that only one switch is switching at a high frequency at a time. This novel inverter design obviates the requirements for a 50/60 Hz low-frequency transformer, consequently enhancing the power density. To validate the theoretical findings, an experimental prototype of the proposed inverter with output voltage ac voltage of peak 155.5 V, line frequency 60 Hz, and an output power of 0.5 kW is implemented. Extensive experimental tests are conducted under various operating conditions. The experimental results validate the theoretical analysis and confirm the practical viability and effectiveness of the proposed topology.