A high‐frequency transformer‐based buck‐boost AC‐AC converter with high efficiency and wide range conversion ratio for DVR application

• Published in: IET power electronics 2024-07, Vol.17 (9), p.1119-1132
• Main Authors: Abdoli, Iman, Ahmed, Hafiz Furqan, Mosallanejad, Ali
• Format: Article
• Language: English
• Subjects: AC‐AC power convertors; compensation; power electronics
• ISSN: 1755-4535; 1755-4543
• DOI: 10.1049/pel2.12487

This paper proposes an isolated single‐phase impedance‐source ac‐ac converter with a wide voltage conversion ratio and a safe commutation strategy. The new topology has noteworthy features like continuous input current, galvanic isolation, and non‐inverting and inverting buck‐boost modes with a wide voltage coverage. Also, only one switch operates with high‐frequency PWM signals, reducing the semiconductor switching loss. The galvanic isolation has been achieved by employing a high‐frequency transformer (HFT), eliminating low‐frequency transformers (LFT) from the topology. A safe commutation strategy has been designed and applied to the converter to mitigate the voltage and current spikes on power switches, which eliminates additional snubber circuits. A prototype has been designed to validate the suggested converter performance in stand‐alone and DVR applications. The peak obtained efficiency equals 96.1% and 94.9% in inverting and non‐inverting step‐down and step‐up modes, respectively, validated by an accurate power loss model and experimental results. Experimental results confirm the theory and operation of the proposed converter. This paper proposed a high voltage gain and efficiency ac‐ac converter with optimized active and passive components for application as DVR.