Novel Current-Mode AC/AC Converters With High-Frequency AC Link-Daolian Chen-Power Electronics Research Institute, Fuzhou University, Fuzhou

Abstract—A novel circuit-topology family of the current-mode ac/ac converter with high-frequency ac link, based on a Flyback converter, is proposed. These circuit topologies, which can transfer one unregulated sinusoidal voltage with high total harmonic distortion (THD) into another regulated constant-frequency sinusoidal voltage with low THD, are composed of input cycloconverter, high-frequency storage transformer, and output cycloconverter. The circuit-topology family includes single fourquadrant power switch mode, push–pull mode, half-bridge mode, and full-bridge mode circuits. The single four-quadrant power switch mode and push–pull mode converters are suitable for low input voltage fields, but the half-bridge mode and full-bridge mode converters are suitable for high input voltage fields. The operational mode, steady principle, and transient voltage feedback control strategy of the kind of converter are investigated. The output characteristic curve, its relation to internal resistance, and the design criteria for the key circuit parameters are given. The theoretical analysis and the test result of the 500 VA 220 V ± 15% 50 HzAC/220 V 50 HzAC prototype have shown that the converters have advantages such as high-frequency galvanic isolation, simple topology, two-stage power conversion [low frequency alternating current (LFAC)/high frequency alternating current (HFAC)/LFAC], bidirectional power flow, high efficiency, high power density, low THD of the output voltage, strong adaptability to various loads, higher line power factor, low audio,noise, etc.

Analysis of Leakage Inductance for Toroidal Type Flyback Transformer Park, Chang-Soo ; Kang, Byeong-Geuk ; Shin, Kyoung-Gu ; Chung, Se-Kyo Dept. of Control and Instrumentation Eng., Gyeongsang

 

Abstract - This paper presents an analysis of a leakage inductance for a toroidal type flyback transformer. The equation to calculate the leakage inductance is derived using the MMF diagram of the transformer. The analysis for the different types of the cores and winding structures is also provided using the FEM simulation. The winding structures minimizing the leakage inductance are finally discussed from the simulation and experimental results.

LINK1
http://www.koreascience.or.kr/search/articlepdf_ocean.jsp?url=http://ocean.kisti.re.kr/downfile/volume/kipe/JRJJC3/2014/v19n2/JRJJC3_2014_v19n2_164.pdf

單階功因修正線路 在發光二極體照明燈具應用之實現 THE IMPLEMENTATION OF SINGLE-STAGE PFC SCHEME FOR THE LED POWER LIGHT APPLICATION

單階功因修正線路
在發光二極體照明燈具應用之實現


THE IMPLEMENTATION OF SINGLE-STAGE PFC SCHEME
    FOR THE LED POWER LIGHT APPLICATION

研究生：鍾任富（Jen-Fu Chung）
指導教授：黃淑絹（Prof. Shu-Chuan Huang）

大同大學
電機工程研究所
    碩士論文
Thesis for Master of Science
Department of Electrical Engineering
Tatung University


ABSTRACT
This thesis mainly presents an implementation of a single-stage Power
Factor Correction (PFC) scheme for the low power LED light application.
As mater of fact, the circuit key idea is from the definition of power factor,
that is the input current must follow the voltage all the time. The PF value is
predicted and set properly by the proposed design equations and circuit
architecture. Detail operation principles, algorithms, and experimental results
are offered, and the experimental results based on 24V 700mA LED down
light prototype schematic are also provided. The final PF value reaches as
high as 0.980 which already satisfied the "ENERGY STAR": PF>0.9 for
commercial application. In addition, the current harmonics were passed in
IEC61000-3-2, too.

Index Terms: Boost Converter, Flyback converter, Single stage PFC.

The Comparison of Conducted Electromagnetic Interference Effect on High Frequency Transformer Winding Techniques

The Comparison of Conducted Electromagnetic Interference Effect on High Frequency Transformer Winding Techniques Tanathep Maneenopphon1, Vuttipon Tarateeraseth2, Werachet Khan-ngern1

Tanathep Maneenopphon1, Vuttipon Tarateeraseth2, Werachet Khan-ngern1 1Faculty of Engineering and EMC Laboratory, Research Center for Communications and Information Technology (ReCCIT) King Mongkut’s Institute of Technology Ladkrabang (KMITL), Bangkok, 10520, Thailand 2Faculty of Engineering, Srinakharinwirot University, Ongkharak, Thailand Phone/Fax: +662 737-3000 Ext. 3322, E-mail: tmn_ta@hotmail.com, vuttipon@swu.ac.th, kkveerac@kmitl.ac.th