Open AccessSelf‐oscillating isolated‐buck (fly‐buck) converter
Author(s) -
Zaikin Denys Igorovych
Publication year - 2021
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/tje2.12060
Subject(s) - buck converter , converters , transformer , buck–boost converter , control theory (sociology) , computer science , electromagnetic coil , oscillation (cell signaling) , voltage , inductor , electrical engineering , engineering , control (management) , artificial intelligence , biology , genetics
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.