Journal of Power Electronics

The Korean Institute of Power Electronics (전력전자학회)
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Analyzing and mitigating parasitic capacitances in planar transformers for high-frequency operation

  • Sujeong Lee (Department of Smart Cities, Chung-Ang University) ;
  • Seokwon Kim (Department of Smart Cities, Chung-Ang University) ;
  • Jong‑Won Shin (Department of Electrical and Computer Engineering, Seoul National University) ;
  • Wonhee Kim (School of Energy System Engineering, Chung-Ang University)
  • Received : 2024.01.25
  • Accepted : 2024.03.15
  • Published : 2024.06.20
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Abstract

Planar magnetic components are compact and less susceptible to skin effect due to their thin copper layers. However, the increase in parasitic capacitance has been a challenge in high-frequency operation of planar transformers (PTs). Parasitic capacitances resonate with inductance and may damage switch devices. Thicker printed circuit board (PCB) and reconfigured windings are suggested in this paper to mitigate the parasitic capacitances. A detailed analysis of the parasitic capacitances is performed with a prototype PT. The resonant frequency increased from 1.27 to 1.63 MHz with a 0.4 mm thicker PCB. The reconfigured PT was 1.38 MHz, 0.3 MHz higher than the original PT.

Keywords

Acknowledgement

This research was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT under Grants RS-2023-00217270 and 2022R1C1C1010027, and Chung-Ang University Graduate Research Scholarship in 2021.

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