返馳切換式整流器之開發及其切換控制

Development of a Flyback Switch Mode Rectifier anf Its Switching Controls

邱韻哲(Yun-Che Chiu)

指導教授 ： 廖聰明

國立清華大學/電機資訊學院/電機工程學系/碩士(2007年)

摘要

本論文旨在研製單級返馳切換式整流器(SMR)，並從事兩種電流控制及其性能比較評估。首先探究電力品質相關事務、現有切換式整流器電路及各式電流模式控制方法。接著從事操作於非連續模式返馳切換式整流器之分析、設計、電路實現及其控制。為便於電路元件之設計選擇，返馳切換式整流器組成關鍵元件之額定值將予以詳細推導。在動態控制研究上，首先從事應用開關電流之平均電流控制。接著介紹所提之變頻電荷調節電流控制切換機構，其開關導通時間為定值，而開關截止時間由低通濾波之開關電流與其命令比較之結果定之，電流命令係由外電壓迴路調控電壓迴授誤差得之。所提電流控制機構無需動態電流控制與從事斜率補償，且具有電流諧波頻譜較分散分佈、強健之電流追蹤控制性能及可應用市售之電壓至頻率轉換積體電路實現等優點。在電壓迴授控制上，本論文推演出一系統化步驟，以從事其動態模式估測，再進而量化設計求出電壓迴授控制之參數。最後，以一些模擬及實測結果展示所建構切換式整流器之性能及所提控制法則之有效性。在本篇論文中建構完成單級單開關切換式整流器，並提出兩種開關電流控制方法。藉由論文探究及回顧，可得知返馳切換式整流器可提供廣範圍且具隔離之輸出直流電。因此，在單級且具良好電力品質調控之交流至直流前端轉換器的使用上是相當不錯的選擇。藉由對於關鍵元件之推導，實現一操作於不連續導通模式下之返馳切換式整流器。為了使切換式整流器獲得良好之電力品質而使用兩種電流控制結構。第一種方法是利用開關電流實現之平均電流控制，另一種是根據電荷調節電流控制的方式來完成。兩種控制方法都可以獲得不錯的電力品質及直流輸出電壓之調控。最後利用模擬及實作之結果來驗證靜態及動態的操作特性。
雖然在返馳切換式整流器之實作上獲得不錯的結果，但仍有許多值得繼續研究之課題: (i) 增進能量轉換之效率; (ii) 發展可以使電流頻譜更分散分佈之變頻式電流控制應用於切換式整流器 (iii)對於切換式整流器之非線性行為做更詳細的研討 (iv) 探討返馳切換式整流器可能的應用。

關鍵字

切換式整流器 ； 功因校正 ； 返馳式轉換器 ； 電流控制 ； 平均電流控制 ； 電荷調控 ； 可變切換頻率 ； 電壓控制

並列摘要

This thesis presents the development of a single-stage flyback switch-mode rectifier (SMR) and performs the comparative study of two current-mode control approaches. The general issues concerning power quality, survey of existing SMR circuits and current mode control methods are first explored. Then the analysis, design, implementation and control of a flyback SMR under discontinuous conduction mode (DCM) are made. For facilitating the circuit component design, the ratings of flyback SMR circuit components are derived in detail. As to the dynamic control studies, the average current control using switch current is first made. Then a varying-frequency charge-regulated approach is developed. Wherein the switch turn-on time is fixed and the off time instant is determined by the low-pass filtered switch current and the current command generated from the outer voltage loop. No dynamic current control and slope compensation are needed. The proposed control scheme possesses the advantages of having dispersedly distributed harmonic spectrum, robust current tracking control, ease of implementation using off-the-shelf integrated circuits, etc. In voltage control loop, the dynamic model is estimated. Then the quantitative feedback controller design is performed by the developed design procedure. Some simulated and experimental results are given to demonstrate the performance of the established SMRs and the effectiveness of the developed control methods.

並列關鍵字

switch-mode rectifier ； power factor correction ； flyback converter ； current control ； average current control ； charge-regulated control ； varying switching frequency ； voltage control ； quantitative controller design

參考文獻

[2] N. Mohan, T. M. Undeland and W. P. Robbins, Power Electronics Converters, Applications and Design, 3rd ed., New York, John Wiley & Sons, Inc., 2003.

[4] L. Moran, P. Werlinger, J. Dixon and R. Wallace, “ A Series active power filter which compensates current harmonics and voltage unbalance simultaneously,” Proc. IEEE PESC ’95, 1995, pp. 222-227.

[5] L. Malesani, L. Rossetto and P. Tenti, “Active power filter with hybrid energy storage,” IEEE Trans. Power Electron., vol. 6, pp. 392-397, 1991.

[6] M. V. Ataide and J. A. Pomilio, “Single-phase shunt active filter: a design procedure considering harmonics and EMI standards,” Proc. IEEE ISIE ’97, 1997, vol. 2, pp. 422-427.

[7] H. Fujita and H. Akagi, “The unified power quality condition: the integration of series-and shunt-active filter,” IEEE Trans. Power Electron., vol. 13, pp.315-322, 1998.