應用動態電壓調整器於感應發電機併聯電力系統

Abstract

隨著石化燃料的逐漸減少而且價格日漸高漲，造成發電的成本越來越高；並伴隨著環保意識的抬頭，各國開始控管溫室效應氣體的排放，提倡使用綠色能源，所以替代能源的開發刻不容緩的進行中。替代能源的種類有許多種，例如風力、太陽能、地熱、潮汐、生質能…等。台灣西部沿海及外島地區擁有相當豐富的風能資源，所以非常適合風力發電的發展。 風力發電機組的主流型式之一為使用感應式發電機組來發電，但是感應機本身有電壓調整能力不佳的缺點，加上風力是時變無法預測的，將使得所發出來的電力不穩定，造成所連接的匯流排電壓不穩定。電力品質對科技產業的影響極大，不穩定的供電將會造成產品不良率的升高及敏感設備的損壞，所以如何改善電力系統的電壓穩定，維持良好的電力品質將是未來電力工程師努力的目標及所面對的問題。 動態電壓調整器是利用弦式脈波寬調變技術來將直流側電容所儲存的能量轉換成交流成份送出，並可以藉由改變輸出電壓的角度，來調整所輸出實、虛功，達到系統電壓控制的目的。將藉由MATLAB/Simulink的模擬，來驗證本論文設計的動態電壓調整器適合應用於感應式發電機併聯系統。

As a result of the price hike in fossil fuels and the effort to control CO2 emissions, developing green energies received much attention in recent years. There are a great variety of green energies such as wind power, solar power, geothermal energy, tide energy, bio-energy,…,etc. Fortunately, Taiwan appears to be a good place to develop of wind power generation, especially in the west coast and the islands around Taiwan. Induction generators have been widely used for wind power generators due to their low cost. When they are driven by a variable speed wind turbine tend to have poor voltage regulation. As a result, how to improve the voltage profile of a wind power generation system is of major concern in this work. To stabilize the output voltage of a wind power generation system, a dynamic voltage regulator, which comprises a voltage source inverter and a dc capacitor, is proposed in this thesis. Through the modulation of the real and reactive power outputs of the DVR, the dc capacitor voltage and the ac system voltage can be held at the specified values. Through dynamic simulations using MATLAB/Simulink, the effectiveness of the proposed dynamic voltage regulator in regulating the output voltage of a wind power generator is demonstrated.