• NANDIKONDA SAIARUN
• GATTU VAMSHI
• PISKA RISHIKESH
• DEVAREDDY HARSHA

LLC resonant converters integrating power factor correction are becoming more common in AC-DC converters. However, single-phase setups often face challenges in effectively controlling the DC bus capacitor voltage during varying line and load conditions. A new approach in this study introduces a unique single-phase AC-DC LLC structure that utilizes a multi-level topology to manage this issue, resulting in a reduced number of switching devices. The innovative three-level inverter design ensures zero voltage switching, thus decreasing circulating current, switching voltage, ripple content and losses. Efficiency is further optimized through a transformer with a bridgeless rectifier system, while power factor correction is achieved by employing a source-side winding for discontinuous current control, nearly achieving unity power factor. By implementing variable switching frequency control for regulating the converter output voltage and utilizing pulse width modulation to govern the multilevel waveform , this system effectively maintains the DC bus voltage within a narrow range across various line and load fluctuations.

LLC resonant converters, AC-DC converters, soft switching, PFC, THD, DC bus.

"AN AC-DC LLC RESONANT CONVERTER WITH POWER FACTOR CORRECTION", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.11, Issue 4, page no.k750-k757, April-2024, Available :http://www.jetir.org/papers/JETIR2404A99.pdf

"AN AC-DC LLC RESONANT CONVERTER WITH POWER FACTOR CORRECTION", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.11, Issue 4, page no. ppk750-k757, April-2024, Available at : http://www.jetir.org/papers/JETIR2404A99.pdf