雙饋型感應風力發電機非線性控制在改善電壓閃爍問題之研究

The Researches of the Nonlinear Control on a Doubly-Fed Induction Wind Generator for the Improvements of Voltage Flicker Problems

孫志偉(Chih-Wei Sun)

指導教授 ： 俞齊山

國立臺北科技大學/電資學院/電機工程系研究所/碩士(2009年)

摘要

當電力系統上有變動性負載時，可能會對系統的電力品質造成嚴重的影響。本論文主要考慮利用雙饋型感應發電機(Doubly-Fed Induction Generator, DFIG)的風力機組，控制其輸出虛功來達到改善系統電壓閃爍(voltage flicker)的效果。為了能有效的控制雙饋型感應發電機，本文首先建構感應機之數學模型，之後將模型的變量利用a-b-c三軸分量轉換為d-q兩軸分量的方式實現本文控制架構的基礎。在設計控制器方面，因為非線性控制較一般線性控制有能在大範圍內直接對非線性作處理的優點，所以本文採用非線性控制中的返步式控制理論(Backstepping theory)設計控制器以達到發電機輸出虛功的控制，而後更進一步利用此控制器改善系統上因變動性負載所造成之電壓閃爍。最後將會以模擬軟體MATLAB/SIMULINK進行分析與驗證，結果顯示本文所設計的控制器確實能有效控制發電機之輸出虛功及改善由變動性負載所造成的電壓閃爍。

關鍵字

雙饋型感應發電機 ； 電壓閃爍 ； 返步式控制 ； 風力發電

並列摘要

When a power system has a fluctuated load, it may have severe impacts on power qualities. The main consideration of this thesis is to control a Doubly-Fed Induction Wind Generator for the improvement of voltage flicker problems. In order to control a DFIG efficiently, this thesis first built the mathematical model of an induction generator. Then, the model was transformed from the a-b-c frame to the d-q two-axis frame to achieve the basic control scheme used in this thesis. In designing the controller, this thesis used backstepping nonlinear control theory to achieve the reactive power control because this controller has the merit to operate in a wide range. Fartherly, the proposed nonlinear reactive power controller was used to improve the impact of voltage flickers caused by fluctuated loads. Finally, the simulation software MATLAB/SIMULINK was adopted to analyze and verify the proposed controller. The results prove that the controller can actually achieve the reactive power control of a DFIG as well as improve voltage flicker problems.

並列關鍵字

Doubly-Fed Induction Generator ； voltage flicker ； backstepping control ； wind power

參考文獻

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