Full-bridge LLC Resonant High-voltage DC–DC Converter with Hybrid Symmetrical Voltage Multiplier

Abstract

This article presents an LLC resonant high-voltage DC–DC converter based on the hybrid symmetrical voltage multiplier that consists of the full-bridge inverter circuit, one resonant tank circuit, one power transformer, and the voltage multiplier circuit. The proposed converter operates below resonance on the negative slope region of DC characteristics curve for realization of zero voltage switching (ZVS) operation. Within this operating region, the power switches and output diodes of the converters generally operate under the ZVS and zero current switching (ZCS) conditions, respectively. The detail structure, design procedure, operation, and steady-state analysis of the proposed converter are thus described. Furthermore, an experimental prototype was built and tested with the input voltage of 100VDC. The results show that the proposed converter is capable to operate under soft-switching conditions, resulting in higher efficiency. The maximum efficiency of the proposed converter of about 96% was recorded at the output power of 550 W.

KEYWORDS:

• DC–DC converter
• LLC resonant converter
• Power transformer
• Resonant tank
• Soft-switching
• Voltage multiplier

Additional information

Funding

The authors would like to thank Universiti Sains Malaysia and Ministry of Higher Education, Malaysia for funding this research project under Research Grant Scheme (FRGS) with project number 203/PELECT/6071307.

Notes on contributors

Nor Azura Samsudin

Nor Azura Samsudin received her BEng in electrical engineering from University Technology MARA, Malaysia in 2008. After two years, she worked as a research officer at the Science & Technology Research Institute for Defence, Malaysia, and continued her postgraduate study and obtained MS and PhD degrees from University Sains Malaysia in 2011 and 2017, respectively. She is currently working as a post-doctoral fellow in the School of Electrical and Electronic Engineering, University Sains Malaysia, Malaysia. Her current research interests include resonant converter and power electronics. Email: [email protected].

Dahaman Ishak

Dahaman Ishak received the BSc degree in electrical engineering from Syracuse University, NY, USA, the MSc degree in electrical power from the University of Newcastle Upon Tyne, UK, and the PhD degree from the University of Sheffield, UK, in 1990, 2001 and 2005, respectively. He is currently an associate professor with the School of Electrical and Electronic Engineering, Universiti Sains Malaysia, Malaysia. His current research interests include high-performance permanent magnet brushless machines, electrical drives, power electronic converters and renewable energy.