臺灣博碩士論文加值系統

本文介紹一種先進的方法，以獲得高功率因數校正（PFC）比傳統的
PFC 電路用的元件還要少。它還提供了一個有效的解決方案，為發光二
極管（LED）供電。高功率因數反激式轉換器在第一階段完全是通過使
用控制器 L6561D 分析。第二個階段是升壓轉換器，它是由控制器
UC3845。 UC3845是峰值電流模式控制，適合作為 LED的電流控制裝置
的控制器。由於改變 UC3845 的佔空比的 PWM 信號，強調 LED 的正向
電流，將滿足 LED 的特性，例如電流和電壓。此外，驅動器和控制電路
T8 - LED 管的結構也設計在這篇論文中進行驗證。一個完整的原型有助
於衡量一些該電路的波形和必要的參數。最後的實驗結果表明，提高功
率因數的 PWM信號的變化。

This thesis introduces an advanced method to get high power factor correction (PFC) with fewer components than the traditional PFC circuits. It also provides an efficient solution to supply power for Light Emitting Diodes (LEDs).
High power factor Flyback converter in first stage is completely analyzed by using the controller L6561D. Second stage is Boost converter which is operated by the controller UC3845. UC3845 is the controller for peak current mode
control which is suitable with current control devices as LED. Because the duty cycle of UC3845 is changed by PWM signal, the forward current stressed on
LED will satisfy the LED’s characteristic such as current and voltage. In addition, the structure of driver and control circuit for T8 – LED tube is also designed and verified in this thesis. A completed prototype helps to measure some waveforms and necessary parameters of this circuit. Finally the experimental results show the improvement of power factor with the variation of
PWM signal.

Abstract .................................................................................................................................................... i
摘要......................................................................................................................................................... ii
Acknowledgements or Preface............................................................................................................... iii
List of table ............................................................................................................................................ vi
List of Figure......................................................................................................................................... vii
Symbols.................................................................................................................................................. ix
Chapter 1 Introduction ......................................................................................................................... 1
Chapter 2 T8 tube LED’s characteristic............................................................................................... 2
2.1 Led introduction ...................................................................................................................... 2
2.2 T8 LED Tube’s application and specifications...................................................................... 4
Chapter 3 The fundamental Boost and flyback converter.................................................................... 7
3.1 The Boost Converter ............................................................................................................... 7
3.1.1 On – time Event................................................................................................................... 8
3.1.2 Off – time event................................................................................................................... 9
3.1.3 Boost waveforms – CCM.................................................................................................... 9
3.2 Fundamentals of Flyback Power Supply Design .................................................................. 12
3.2.1 Transfer of Energy............................................................................................................. 12
3.2.2 Summary of Fundamentals................................................................................................ 17
Chapter 4 L6561D and UC3845 parameters...................................................................................... 18
4.1 L6561D specifications........................................................................................................... 18
4.1.1 Features............................................................................................................................. 18
4.1.2 Descriptions....................................................................................................................... 19
4.2 UC3842/3/4/5 Current mode PWM controller...................................................................... 21
4.2.1 Feature............................................................................................................................... 21
4.2.2 Description. ....................................................................................................................... 21
Chapter 5 Active power factor correction introduce.......................................................................... 27
5.1 Power factor definition.......................................................................................................... 27
5.2 Non-Linear Load and Power Factor...................................................................................... 30
5.3 Active Power Factor Correction............................................................................................ 34
5.4 Input Distortion Sources........................................................................................................ 39
Chapter 6 Design Flyback converter with L6561D ........................................................................... 42
6.1 Introduction ........................................................................................................................... 42
6.2 Timing relationships.............................................................................................................. 48
6.3 Energetic relationships.......................................................................................................... 50v
6.4 Power Factor and Total Harmonic Distortion........................................................................ 55
6.5 Transformer........................................................................................................................... 56
6.6 Clamp network ...................................................................................................................... 57
6.7 Output Capacitor ................................................................................................................... 58
6.8 Multiplier Bias and Sense Resistor Selection........................................................................ 59
6.9 Closing the Control Loop...................................................................................................... 60
Chapter 7 Dimming Techniques for Switched-Mode LED Drivers .................................................. 64
7.1 Introduction ........................................................................................................................... 64
7.2 LED Dimming Methods........................................................................................................ 64
7.2.1 Analog dimming circuit..................................................................................................... 65
7.2.2 PWM dimming circuit....................................................................................................... 65
Chapter 8 Experimental Results......................................................................................................... 66
8.1 The schematic........................................................................................................................ 66
8.2 The experimental circuit........................................................................................................ 67
8.3 The performance of the circuit. ............................................................................................. 67
Chapter 9 Conclusions....................................................................................................................... 71
Referencens........................................................................................................................................... 72
Abstract ................................................................................................................................................. 73
Curriculum Vitae (CV).......................................................................................................................... 78

[1] M. S. Shur and A. Zukauskas, “Solid-state lighting: Toward superior
illumination,” Proc. IEEE, vol. 93, no. 10, pp. 1691–1703, Nov. 2005.
[2] J. Y. Tsao, “Solid-state lighting: Lamps, chips and materials for
tomorrow,” IEEE Circuits Devices Mag., vol. 20, no. 3, pp. 28–37,
May/Jun.2004.
[3] M. Wendt and J. W. Andriesse, “LEDs in real lighting applications:
From niche markets to general lighting,” in Proc. IEEE IAS, 2006, pp.
2601–2603.
[4] D. A. Steigerwald, J. C. Bhat, D. Collins et al., “Illumination with solid
state lighting technology,” IEEE J. Sel. Topics Quantum Electron., vol.
8,no. 2, pp. 310–320, Mar./Apr. 2002.
[5] G. Carraro, “Solving high-voltage off-line HB-LED constant-current
control-circuit issues,” in Proc. IEEE APEC, 2007, pp. 1316–1318.
[6] M. Nishikawa, Y. Ishizuka, H. Matsuo, and K. Shigematsu, “An LED
drive circuit with constant- output-current control and constantluminance control,” in Proc. INTELEC, 2006, pp. 1–6.
[7] Energy
�
. Program Requirements for Solid State Lighting
Luminaires.Eligibility Criteria - Version 1.1, USA (2008). [Online].
Available:http://www.energystar.gov/index.cfm?c=new_specs.ssl_lumin
aires
[8] "Design Equations of High-Power-Factor Flyback Converters Based on
the L6561" (AN1059)
[9] “UC3854 Controlled Power Factor Correction Circuit Design” (U134)