雙級伺服器電源的控制技術發展

Development of Control Techniques for Two-Stage Server Power

蘇子杰(Zih-Jie Su)

指導教授 ： 賴炎生

國立臺北科技大學/電資學院/電機工程系博士班/博士(2014年)

摘要

本論文旨在發展雙級伺服器電源的控制技術，本文所使用的伺服器電源有兩種架構，其一是由功率因數修正器及相移全橋轉換器所組成，另一種則是由因數修正器及LLC諧振轉換器所組成。為改善雙級伺服器電源的效率，本論文提出數種控制技術，包含：1. 線上最大責任週期追蹤技術，此技術為調整功率因數修正器輸出的直流鏈電壓，使得相移全橋轉換器的責任週期可維持在最大值，降低相移全橋轉換器的環流損失及切換損失，進而提升伺服器電源的效率。2. 為了符合輸入電源失去時，其輸出電壓所需維持時間規範，本論文提出一混合式控制技術，在輕載時，使用線上最大責任週期追蹤技術來改善其效率，並且在重載時將直流鏈電壓提升到額定電壓，使得相移全橋轉換器的輸出可以達到所需之維持時間規範。3. 為了改善輕載的功率損耗，本論文提出一新型整合控制技術，利用切換控制技術及最大責任週期追蹤技術，減少伺服器電源輕載時的功率損耗。4.本論文提出一線上直流鏈電壓調變技術，應用於LLC諧振轉換器，將LLC諧振轉換器的切換頻率控制在諧振頻率附近，以減少額外的循環損失或開關截止的切換損失。
所提出雙級伺服器電源的控制技術，均以數位控制器實現，實驗系統規格包含輸入電壓 AC 110 V / 220 V、輸出電壓 DC 12 V、額定功率 480 W。實驗結果證實本論文所提之控制方法的可行性。

關鍵字

伺服器電源 ； 功率因數修正器 ； 相移全橋轉換器 ； LLC諧振轉換器

並列摘要

The main theme of this dissertation is to develop the control techniques of two-stage server power. Two types of server power, consisting of Power Factor Corrector (PFC) and Phase Shift Full-Bridge (PSFB) converter, and PFC and LLC resonant converter, are used in this dissertation. In order to improve the efficiency, several control techniques are proposed in this dissertation. First, a novel on-line maximum duty point tracking (MDPT) technique to control the DC-link voltage of the PFC to retain the maximum duty of the PSFB converter is proposed to reduce the circulating loss and switching losses of the converter. Second, in order to meet the hold-up time requirement, a hybrid control technique is proposed, the DC-link voltage is controlled to be its nominal value under heavy load conditions to meet the hold-up time requirement, while being reduced under light load condition to improve its efficiency. Third, in order to improve light load efficiency, a new integrated control technique is proposed, the switching control and MDPT techniques are proposed to reduce the power consumption under light load condition. Finally, an on-line DC-link voltage control technique is proposed for LLC converter of server power to improve efficiency. The proposed on-line control technique controls the DC-link voltage of power factor corrector (PFC) to limit the switching frequency of LLC resonant converter around its resonant frequency in order to reduce the additional circulating loss or turn-off switching loss.
The proposed control techniques are realized by digital signal processor. The specifications of the experimental system include: AC input voltage = 110 / 220 V, DC output voltage = 12 V and rated power = 480 W. The experimental results confirm the effectiveness of the proposed control techniques.

並列關鍵字

Server Power ； Power Factor Corrector ； Phase-Shift Full-Bridge Converter ； LLC Resonant Converter ； DC-link Voltage Control Technique

參考文獻

[5] M. M. Jovanović and Y. Jang, “State-of-the-art, single-phase, active power-factor-correction techniques for high-power applications—An overview,” IEEE Trans. on Industrial Electron., vol. 52, no. 3, pp. 701-708, Jun. 2005.

[6] A. Miwa, D. M. Otten and M. E. Schlecht,“High efficiency power factor correction using interleaving techniques,” in Proc. IEEE APEC, Feb. 1992, pp. 557-568.

[7] K. Y. Lee and Y. S. Lai, “Novel circuit design for two-stage AC/DC converter to meet standby power regulations,” IET Power Electron., vol. 2, no. 6, pp. 625-634, Nov. 2009.

[8] J. Sebastián, D. G. Lamar, A. Rodríguez-Alonso, M. A. P. de Azpeitia and A. F. Gonzalez, “On the maximum bandwidth attainable by power factor correctors with a standard compensator,” IEEE Trans. on Ind. Appl., vol. 46, no. 4, pp.1485-1497, July-Aug. 2010

[9] Y. S. Lai, K. M. Ho and B. Y. Chen, “Bandwidth-based analysis and controller design of power factor corrector for universal applications,” In Proc. IEEE ICIT, pp. 626-631, 2012.