design, application and comparison of single stage flyback and sepic pfc ac/dc converters for ...

217 Pages·2012·5.16 MB·English

DESIGN, APPLICATION AND COMPARISON OF SINGLE STAGE FLYBACK
AND SEPIC PFC AC/DC CONVERTERS FOR POWER LED LIGHTING
APPLICATION

A THESIS SUBMITTED TO
THE GRADUATE SCHOOL OF NATURAL APPLIED SCIENCES
OF
MIDDLE EAST TECHNICAL UNIVERSITY

BY

HASAN YILMAZ

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR
THE DEGREE OF MASTER OF SCIENCE
IN
ELECTRICAL AND ELECTRONICS ENGINEERING

SEPTEMBER 2012
Approval of the thesis:

DESIGN, APPLICATION AND COMPARISON OF SINGLE STAGE
FLYBACK AND SEPIC PFC AC/DC CONVERTERS FOR POWER LED
LIGHTING APPLICATION

Submitted by HASAN YILMAZ in partial fulfillment of the requirements for the
degree of Master of Science in Electrical and Electronics Engineering
Department, Middle East Technical University by,

Prof. Dr. Canan Özgen
Dean, Graduate School of Natural and Applied Sciences

Prof. Dr. İsmet Erkmen
Head of Department, Electrical and Electronics Engineering

Assoc. Prof. Dr. Ahmet M. Hava
Supervisor, Electrical and Electronics Engineering Dept., METU

Examining Committee Members:

Prof. Dr. Muammer Ermiş
Electrical and Electronics Engineering Dept., METU

Prof. Dr. Arif Ertaş
Electrical and Electronics Engineering Dept., METU

Assoc. Prof. Dr. Ahmet M. Hava
Electrical and Electronics Engineering Dept., METU

Assist. Prof. Dr. Umut Orguner
Electrical and Electronics Engineering Dept., METU

Eyyüp Demirkutlu, M.Sc.
GUCELSAN, General Manager

Date: 13/09/2012
I hereby declare that all information in this document has been obtained and
presented in accordance with academic rules and ethical conduct. I also declare
that, as required by these rules and conduct, I have fully cited and referenced
all material and results that are not original to this work.

Name, Last name : Hasan Yılmaz

Signature :

iii
ABSTRACT

DESIGN, APPLICATION AND COMPARISON OF SINGLE STAGE FLYBACK
AND SEPIC PFC AC/DC CONVERTERS FOR POWER LED LIGHTING
APPLICATION

Yılmaz, Hasan
M.S., Department of Electrical and Electronics Engineering
Supervisor: Assoc. Prof. Dr. Ahmet M. Hava

September 2012, 199 pages

In this work, single stage power factor corrected AC/DC converters for LEDs; single
stage Flyback converter having different configuration from the traditional Flyback
and single stage SEPIC converter is investigated. The study involves analysis, circuit
design, performance comparisons and implementation. The study covers LEDs; their
developments, characteristics and state-of-art in this new technology. The circuits are
investigated by means of computer simulations. Operating principles and operating
modes are studied along with design calculations. After applying prototypes in
laboratory, the simulation results and theoretical analyses are confirmed. The single
stage Flyback converter has high voltage input (220-240 Vac), and the output feeds
up to 216 HB-LEDs, with the ratings of 24 V, 3.25 A with 90 W. The single stage
SEPIC converter with universal input (80-265 Vac) has an output that feeds 21
power LEDs, with 67 V, 0.30 and 20 W ratings.

Keywords: Power factor correction, single-stage power supply, LED, LED driver,
AC-DC converter

iv
ÖZ

TEK KATLI FLYBACK VE SEPIC GKD’LERİN GÜÇ LED’İYLE
AYDINLATMA UYGULAMASI İÇİN TASARIMI GERÇEKLENMESİ VE
KARŞILAŞTIRILMASI

Yılmaz, Hasan
Yüksek Lisans, Elektrik Elektronik Mühendisliği Bölümü
Tez Yöneticisi: Doç. Dr. Ahmet M. Hava

Eylül 2012, 199 sayfa

Bu çalışmada Güç LED’ i (G-LED) ile aydınlatma uygulaması için güç katsayısı
düzeltici AC/DC güç kaynaklarından geleneksel yapıdan farklılık gösteren tek katlı
Flyback ve SEPIC devreleri ele alınacaktır. Bu devrelerin analizi, tasarımı, deneysel
gerçeklenmesi ve başarımlarının karşılaştırılması yapılacaktır. Çalışma içerisinde
LED gelişimi, karakteristik özellikler ve öne çıkan özellikleri detaylandırılmıştır.
Çalışmada devreler ayrıntılı bilgisayar benzetimleri ile incelenecek, çalışma ilkeleri
ve çalışma kipleri detaylandırılacak, tasarım hesapları yapılacaktır. Çalışmada, söz
konusu devrelerin teoriye ve bilgisayarla benzetime dayalı inceleme sonuçları
deneysel ilk örneklerin laboratuarda uygulanması ile deneysel sonuçlarla
doğrulanacaktır. Çalışmada yüksek gerilim girişli (220-240 Vac) 216 HB-LED
sürebilen 24 V, 3.25 A çıkışlı 90 W gücünde tek katlı Flyback devresi ve evrensel
girişli ( 85-265Vac) 21 LED sürebilen 67 V, 0.30 A çıkışlı 20 W tek katlı SEPIC
devresi incelenecektir.

Anahtar kelimeler: Güç katsayısı düzeltimi, tek-katlı güç kaynakları, LED, LED
sürücü, AC-DC çevirici

v
To my family and
Memory of my grandfathers,
Hasan Yılmaz and Muzaffer Arıcı

vi
ACKNOWLEDGMENT

I express my sincerest thanks to my supervisor, Assoc. Prof. Dr. Ahmet M. Hava, for his
guidance, support and encouragement. Beside the technical developments, he thought me the
advances of power electronics and the methodology of a research.

I would like to express my gratitude to my family, for their support to my graduate
education.

I would like to express my gratitude to my managers and colleagues at BAHAR Aydinlatma
and Siber LED for their understanding, help and support. I am grateful to my engineer
colleague Mustafa Yüksel, to his help in the experiments.

I wish to thank the Department of Electrical and Electronics Engineering faculty and staff
and Graduate School of Natural and Applied Sciences for this opportunity to advance in our
profession.

vii
TABLE OF CONTENTS

ABSTRACT………….………………………………………………………………………iv
OZ………………………………………………………………………………………….…v
DEDICATION……………………………………………………………………………….vi
ACKNOWLEDGMENT…………………………………………………………………….vii
TABLE OF CONTENTS…………………………………………………………………...viii
LIST OF FIGURES……………………………………………………………………...…xiii
LIST OF TABLES…………………………………………………………………….......xviii

CHAPTERS

1. INTRODUCTION ................................................................................................ 1

1.1 General ..................................................................................................... 1
1.2 Single-Stage PFC Power Supply .............................................................. 5
1.3 Scope of Thesis ........................................................................................ 6
2. NEW LIGHT SOURCE: LEDS .............................................................................. 8
2.1 Introduction .............................................................................................. 8
2.2 LEDs; Definition and Development ......................................................... 9
2.3 LEDs Structure and Electrical Characteristics ....................................... 12
2.4 State of Art of LEDs ............................................................................... 17
2.4.1 Advantages ............................................................................. 17
2.4.2 Disadvantages ......................................................................... 19
2.4.3 Comparison............................................................................. 20
2.5 Light Definition and Terms .................................................................... 21
2.6 LEDs Electrical and Thermal Model ...................................................... 25
2.6.1 LED Electrical Model ............................................................. 25
2.6.2 LED Thermal Model .............................................................. 27

viii
2.7 LED Drive Requirements ....................................................................... 32
2.7.1 Passive Current Control .......................................................... 35
2.7.2 Active Current Control ........................................................... 36
2.7.3 Standards ................................................................................ 37
3. POWER SUPPLY TOPOLOGIES FOR LEDS .................................................... 39
3.1 Introduction ............................................................................................ 39
3.2 AC-DC Converters for LED Driver ....................................................... 41
3.2.1 General ................................................................................... 41
3.2.2 AC-DC Power Supply Special Properties for LED
Applications ..................................................................................... 44
3.2.2.1 AC-DC Power Supply Protection - Lightning ..... 44
3.2.2.1 AC-DC Power Supply Application - Dimming ... 45
3.2.2.2 AC-DC Power Supply Protection - EMI ............. 46
3.2.2.3 AC-DC Power Supply Power Quality ................. 46
3.3 Power Factor Correction ........................................................................ 47
3.4 DC Drive Circuits for LED .................................................................... 49
3.4.1 Linear Drivers ......................................................................... 49
3.4.2 DC-DC Converters ................................................................. 49
3.4.2.1 Fundamental Converters ...................................... 51
3.4.2.1.1 Buck Converter LED Drivers ................. 52
3.4.2.1.2 Boost Converter LED Drivers ................ 56
3.4.2.1.3 Buck-boost Converter LED Driver ......... 59
3.4.2.2 Transformer-Type Converters ............................. 63
3.4.2.2.1 Flyback Converter ................................... 63
3.4.2.2.2 Forward Converter .................................. 65
3.5 Power Factor Correction Stages ............................................................. 67
3.5.1 Passive Power Factor Correction ............................................ 67
3.5.2 Active Power Factor Correction ............................................. 68
3.5.3 Two-Stage AC-DC Converter for LED Driver ...................... 72

ix
3.6 Single-stage Power Factor Correction AC/DC LED drivers .................. 73
3.6.1 Introduction ............................................................................ 73
3.6.2 Review of Single Stage Power Factor Correction Power
Supplies ........................................................................................... 74
3.6.3 Single Stage PFC Power Supplies Drawbacks and Solutions 79
3.7 Three Special PFC AC/DC LED Drivers ............................................... 79
3.7.1 Single-Stage Flyback Power-Factor-Correction Front-End for
HB LED Application [26] ............................................................... 80
3.7.2 Design Considerations of High Power Factor SEPIC Converter
for High Brightness White LED Lighting Applications [29] .......... 81
3.7.3 Single Stage Flyback LED Driver: RECOM RACD - 30-700 82
4. DESIGN AND IMPLAMENTATION OF SINGLE STAGE HIGH POWER
FACTOR SEPIC CONVERTER FOR LED APPLICATIONS ............................... 84
4.1 Review of SEPIC topology .................................................................... 84
4.1.1 DC Analysis of SEPIC converter ........................................... 86
4.2 Single-stage High Power Factor AC-DC SEPIC LED Driver ............... 88
4.2.1 Introduction ............................................................................ 88
4.2.2 Converter Operation Mechanism............................................ 89
4.3 Design of Single-Stage SEPIC AC/DC Converter ................................. 94
4.3.1 AC-DC SEPIC Converter Working Conditions ..................... 95
4.3.2 AC-DC SEPIC Converter Specifications ............................... 97
4.3.2.1 Step 1: Duty cycle calculation ............................. 98
4.3.2.2 Step 2: Passive Component Selection ................ 100
4.3.2.3 Step 3: Active Components Selection ............... 101
4.3.2.3.1 ISL6745, Bridge Controller with Precision
Dead Time ........................................................... 101
4.3.2.3.2 MOSFET Selection ............................... 105
4.3.2.3.3 Diode selection ..................................... 109

x