Analysis of fly‐buck converter with emphasis on its cross‐regulation

Wu, Wei; Lu, Dexiang; Chai, Qinqin; Lin, Qiongbin; Cai, Fenghuang

doi:10.1049/iet-pel.2016.0272

Cited by 16 publications

(11 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For reference [11] it is necessary to develop an RCD snubber to absorb the energy of leakage inductance. References [12][13][14][15][17][18][19] require an expensive controller to implement. References [16,21] require a transformer for each output.…”

Section: Experiments Results and Discussionmentioning

confidence: 99%

“…Reference [18] adopts 5 switches to achieve two outputs voltage which are regulated independently and not affected by the variation of load current. Vo1 presents the fly-buck [19] converter in buck mode, and Vo2 in flyback mode, then realizes lower cross-regulation. The primary side uses a half-bridge inverter, and the secondary side uses a flyback rectifier combined auxiliary buck converter to implement two outputs without cross-regulation problems [20].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Three-Output Flyback Converter with Synchronous Rectification for Improving Cross-Regulation and Efficiency

Leng

Chiu

2021

Electronics

View full text Add to dashboard Cite

This paper proposes a single stage alternating current/direct current (AC/DC) flyback converter which contains three output windings with synchronous rectification (SR) function to achieve better cross-regulation and efficiency. Because the three output windings are stacked in a series structure and use synchronous rectification instead of diode rectification, the forward conduction loss of the diode can be eliminated, and the current of each winding can flow bilaterally. Therefore, the energy of leakage inductance can be dissipated through heavy load winding without transient overvoltage in light load winding. Compared with existing methods in the literature, the proposed converter can be realized by simple analog IC with fewer winding turns. Finally, under the extreme load imbalance condition, the cross-regulation is still within ±2.26%. The maximum efficiency of the proposed converter reaches 87%, which is about 3% higher than the conventional Schottky diode solution’s efficiency. The circuit structure and operation principle are described. A practical prototype and experiment results are implemented to verify the feasibility of the proposed converter.

show abstract

Section: Experiments Results and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Three-Output Flyback Converter with Synchronous Rectification for Improving Cross-Regulation and Efficiency

Leng

Chiu

2021

Electronics

View full text Add to dashboard Cite

show abstract

“…The turn ratios 1 ∶ N Q1 and 1 ∶ N Q2 defined by Equations (19) and (20) are minimum values that may be corrected due to the effect of the leakage inductance of the main transformer T1. In multi-winding transformers, the transformer model contains leakage inductances in series with each winding (T-model [15]).…”

Section: Gate Drive Windingsmentioning

confidence: 99%

“…If the turn rations for the auxiliary windings have been chosen optimally, as outlined in Section 3.2 with Equation ( 19) and (20), the gate voltage only briefly remains at the V zener limit. Thus, it is assumed that…”

Section: Switching Frequency and Duty Cycle Calculationmentioning

confidence: 99%

Self‐oscillating isolated‐buck (fly‐buck) converter

ZAIKIN¹

2021

The Journal of Engineering

View full text Add to dashboard Cite

This study presents a self-oscillating fly-buck converter. The primary objective of this research is to lower the final bill of materials cost of a fly-buck converter. The fly-buck converter is based on a relaxation self-oscillation circuit. The main transformer is updated with two additional auxiliary windings for positive feedback implementation. The turn ratios of these windings are estimated, and criteria for a stable oscillation mode are developed. A switching frequency formula is also provided. Furthermore, an example start-up circuit is proposed and calculated. Output voltage stabilisation is implemented and demonstrated to work with ±10% variations in input voltage. The experimental data and design procedure are presented along with a comparison of the proposed fly-buck converter against conventional fly-buck converters. The converter is optimised for maximum efficiency, with an efficiency of > 85% demonstrated at 20 W output power. The proposed self-oscillating circuit can also be implemented in a conventional synchronous buck converter. The Maxima software code for automated calculation of the converter is supplied as supplemental active media content.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

show abstract

“…Only one of the outputs is controlled, causing severe cross-regulation issues for the second output. In order to remediate the cross-regulation problem, adding an active switch to the secondary of the coupled inductor was proposed in [19].…”

Section: Two-output Fly-buck Convertermentioning

confidence: 99%

Multiple-Output DC-DC Converters with a Reduced Number of Active and Passive Components

Turhan

Castellanos

Hendrix

et al. 2019

JLPEA

View full text Add to dashboard Cite

Multiple-output converters have been widely used where individual outputs are required. Compared with conventional separate converters, the advantage of multiple outputs is to have a lower number of active and passive components. In this paper, first, a pulse-width-modulation (PWM)-pulse-frequency-modulation (PFM) method is used for two-output converters that have only one coil and one active switch. Secondly, three-output converter topologies are proposed where the third output is controlled by phase delay (PD). These converters need only two coils and two active switches to regulate three outputs. How to obtain PD at different switching frequencies is discussed next, and a PWM-PFM-PD controlled five-output buck converter is presented. The proposed solution uses only two active switches and two magnetic cores to adjust five-output voltages independently. A modeling and digital control method are proposed in order to regulate the five output voltages. A prototype circuit with independent 15 V/1.5 A, 12 V/1.5 A, 5 V/0.8 A, −5 V/0.6 A and 3.3 V/0.45 A outputs is assembled to validate the analysis, and it was proved that it regulates the output voltages at different loads.

show abstract

Analysis of fly‐buck converter with emphasis on its cross‐regulation

Cited by 16 publications

References 21 publications

Three-Output Flyback Converter with Synchronous Rectification for Improving Cross-Regulation and Efficiency

Three-Output Flyback Converter with Synchronous Rectification for Improving Cross-Regulation and Efficiency

Self‐oscillating isolated‐buck (fly‐buck) converter

Multiple-Output DC-DC Converters with a Reduced Number of Active and Passive Components

Contact Info

Product

Resources

About