Abstract
The demand of miniaturization of power systems has accelerated the research on high-switching-frequency power converters. A flyback converter in resonant mode that features low switching losses, less transformer losses, and low switching noise at high switching frequency is investigated in this paper as an alternative to a conventional quasi-resonant (QR) flyback topology to increase power density. In order to find a compromise between magnet size, electromagnetic interference (EMI), and efficiency, the concept utilizes the resonant behavior between transformer leakage inductance and snubber capacitor to achieve near-zero-voltage switching at both turn-on and turn-off of the primary switch, low core loss due to a continuous transformer magnetizing current, and reduced EMI due to low di/dt and dv/dt values. Meanwhile, the concept uses the regenerative snubber to recycle the transformer leakage energy with two snubber diodes and one snubber capacitor. The proposed concept has been validated on a 340-kHz 65-W prototype. Compared to the conventional QR flyback converter operating at the same switching frequency, the proposed concept has 2% efficiency improvement and better EMI performance.
Original language | English |
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Article number | 7792114 |
Pages (from-to) | 8582-8592 |
Number of pages | 11 |
Journal | IEEE Transactions on Power Electronics |
Volume | 32 |
Issue number | 11 |
DOIs | |
Publication status | Published - 1 Nov 2017 |
Keywords
- Flyback
- high switching frequency
- regenerative snubber
- resonant power conversion
- switching loss