Analysis, design, and performance evaluation of asymmetrical half-bridge flyback converter for universal-line-voltage-range applications

In this article, an innovative power adaptor based on the asymmetrical pulse width modulation (PWM) flyback topology will be presented. Its benefits compared to other state-of-the-art topologies, such as the active clamp flyback, are analyzed in detail. It will also describe the control methods to achieve high efficiency and power density using zero-voltage switching (ZVS) and zero-current switching (ZCS) techniques over the full range of the input voltage and the output load, providing comprehensive guidelines for the practical design. Finally, we demonstrate the convenience of the proposed design methods with a 65 W adaptor prototype achieving a peak efficiency of close to 95% and a minimum efficiency of 93.4% at full load over the range of the input voltage, as well as a world-class power density of 22 W/inch3 cased.

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“…As described in detail in [11,12], the proposed topology provides an output voltage proportional to the duty cycle, according to:…”

Section: Duty Cycle and Output Voltagementioning

confidence: 99%

Resonant Hybrid Flyback, a New Topology for High Density Power Adaptors

et al. 2018

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“…The asymmetric half-bridge (AHB) flyback converter has been proposed in previous studies [20][21][22][23][24][25][26][27][28][29], whose main advantage is that the number of components is the same as that of ACF converter, and it also provides the same voltage stress on the switching that of ACF converter, and it also provides the same voltage stress on the switching elements as the LLC converter with ZVS turn-on. Most studies of AHB flyback converters adopt pulse width modulation (PWM) control.…”

Section: Introductionmentioning

confidence: 99%

“…However, previous researches in [20][21][22][23][24][25][26][27] suggest that PWM should not be used because Toff of PWM mode varies with the input voltage and load condition to affect the ZVS operation range. In [28], the AHB flyback converter is unstable with the PWM control method.…”

Section: Introductionmentioning

confidence: 99%

Resonant Asymmetrical Half-Bridge Flyback Converter

Yau

2022

Applied Sciences

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The active clamp flyback (ACF) converter is gradually becoming popular in the application field of low or medium output power range due to its advantage of soft switching and high conversion efficiency. An asymmetric half-bridge (AHB) flyback converter has been proposed in previous studies. The main advantages of the AHB flyback are the same number of components as the ACF converter and the soft switching technique. In this paper, an AHB flyback converter with constant off-time (COT) plus pulse frequency modulation (PFM) is proposed, so that the resonant time is not affected by the input voltage and load, and can achieve a wide range of zero voltage switching (ZVS) operating range. Compared to pulse width modulation (PWM), the PFM control with COT can make the system more stable. Finally, a prototype circuit with a specification input of 48 V to an output of 2.5 V/8 A is made for verification.

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“…Fly-buck converters [9], [10], [19] realize a much higher input-voltage scaling with a lower amount of components, due to the flexible dimension of the transformer's turns ratio n, but they still need a large external HV capacitor C HV at the primary side [see Fig. 2 (center)] and a large transformer T.…”

Section: Introductionmentioning

confidence: 99%

A Resonant One-Step 325 V to 3.3–10 V DC–DC Converter With Integrated Power Stage Benefiting From High-Voltage Loss-Reduction Techniques

Rindfleisch

Wicht

2021

IEEE J. Solid-State Circuits

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This work presents a self-timed resonant highvoltage (HV) dc-dc converter in HV CMOS silicon-on-insulator (SOI) with a one-step conversion from 100-325 V input down to a 3.3-10 V output, optimized for applications below 500 mW, such as IoT, smart home, and e-mobility. Unlike bulky power modules, the HV converter is fully integrated, including an on-chip power stage, with only one external inductor (10 µH) and capacitor (470 nF). It reaches a high power density of 752 mW/cm 3 , an overall peak efficiency as high as 81%, and a light-load efficiency of 73.2% at 5 V and 50 mW output. HV loss-reduction techniques are presented and experimentally confirmed to offer an efficiency improvement of more than 32%. Integrated HV insulated gate bipolar transistors (IGBTs) are discussed and implemented as an attractive alternative to conventional integrated HV power switches, resulting in ∼20% smaller area at lower losses.

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Analysis, design, and performance evaluation of asymmetrical half-bridge flyback converter for universal-line-voltage-range applications

Cited by 17 publications

References 13 publications

Resonant Hybrid Flyback, a New Topology for High Density Power Adaptors

Resonant Hybrid Flyback, a New Topology for High Density Power Adaptors

Resonant Asymmetrical Half-Bridge Flyback Converter

A Resonant One-Step 325 V to 3.3–10 V DC–DC Converter With Integrated Power Stage Benefiting From High-Voltage Loss-Reduction Techniques

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