考量電力系統電壓不平衡與驟降時靜態同步補償器之雛形設計與實作

Design and Implementations of STATCOM Prototypes with Considering Unbalanced Voltage Sags in Power Systems

曾聖然(Sheng-Jan Tseng)

指導教授 ： 朱家齊

國立清華大學/電機資訊學院/電機工程學系/碩士(2010年)

摘要

由於高科技產業之興起，自動化設備大量使用於工業界，所以電力品質的要求也越來越高，而在電力系統中常見的電壓驟降及電壓不平衡情形，通常是由劇烈變動之高功率負載或系統故障等原因所引起，往往會導致自動化設備的損壞或誤動作。靜態同步補償器具有動態響應速度快、電流諧波含量小、裝置體積小等優點，而對於電力品質問題有非常良好的改善效果。 本論文探討靜態同步補償器，在系統平衡與不平衡情況下的控制策略，以電壓源變流器為基礎，建立三相110V 1KVA之小型實驗室雛型平台，完成相關控制策略之設計，並以電磁暫態模擬器PSCAD軟體模擬與硬體實驗交互驗證，以確保控制系统的有效性。理論部分將利用同步旋轉座標，建立靜態同步補償器在旋轉座標下的正、負序之動態模型，確保於系統責任分界點發生平衡與不平衡電壓驟降、或平衡與不平衡負載切換時，負載匯流排之電壓支持策略。控制策略應用內外雙迴圈之解耦閉迴路控制架構：內迴圈完成電流命令追蹤，外迴圈完成匯流排交流電壓與電壓源變流器直流鏈電壓命令追蹤。軟體模擬與硬體實作驗證該控制架構優異之穩態與暫態性能。 關鍵詞: 電壓驟降、電壓不平衡、電力品質、靜態同步補償器、同步旋轉座標理論、內外雙迴圈之解耦閉迴路控制、實驗室雛型平台。

關鍵字

電壓驟降 ； 電壓不平衡 ； 電力品質 ； 靜態同步補償器 ； 同步旋轉座標理論 ； 內外雙迴圈之解耦閉迴路控制 ； 實驗室雛型平台

並列摘要

Due to heavily load fluctuations or unexpected faults in power systems, voltage sags and unbalanced problems are one of the important issues for power distribution systems, especially for sensitive loads such as high-tech industrial parks. In recent years, due to rapid development of high-power electronics technology, it is possible to provide such voltage supports during the very short transient period by installing Static Synchronous Compensators (STATCOMs). When either the balanced or unbalanced voltage sag occurs in the point of common connection (PCC) of the system, or loads switching in the load bus, this STATCOM will provide adequate voltage supports.
This thesis will report hardware implementations of a small laboratory-scale STATCOM. The rating of this three-phase STATCOM is 110 V, and 1 KVA. By applying the Synchronous Reference Frame (SRF) theory, the mathematical model of the STATCOM under the positive sequence and the negative sequence are described. The inner/outer two-loop decoupled control strategy is explored. The inner loop control is for the current command tracking while the outer loop control is for the bus AC voltage and the DC-link voltage control. The proposed control configuration has been validated under PSCAD simulations and hardware laboratory implementations. Experimental works on various operating conditions have been conducted to verify the effectiveness of the proposed control strategy.

Keywords: Voltage Sags, Unbalanced Systems, Static Synchronous Compensator (STATCOM), Synchronous Reference Frame (SRF), Decoupled Control, Laboratory Platform Implementations.

並列關鍵字

Voltage Sags ； Unbalanced Systems ； Static Synchronous Compensator ； Synchronous Reference Frame ； Decoupled Control ； Laboratory Platform Implementations

參考文獻

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