雙饋式感應發電機具有變速恆頻之性能，且降低所需電力轉換器之額定功率，特別適用於經常變速的風力發電系統之特性，並可藉此控制發電機輸出實功功率及虛功功率，因此採用合適的激磁控制策略是雙饋式感應發電機能夠發揮其良好的調節性能、操作的靈活性及可靠性的關鍵。而對於雙饋式感應發電機之磁場導向控制策略目前已有初步的理論分析與實驗證明，現有技術多半需要轉速感測器。本文探討合適的無感測器理論應用於雙饋式感應發電系統，達成相近系統控制效能之目標下，減少轉速感測器成本支出。
本論文將以雙饋式感應發電機的向量控制為基礎，探討相關無感測型向量控制，貢獻有下列三點：
1. 建構雙饋式感應發電機的基本模型架構以及介紹定子磁交鏈之電壓與電流模型，並推導出廣義磁交鏈之相互關係，及建構雙饋式感應發電機之定子磁場導向控制模擬架構，為無感測型控制器理論之模型奠定基礎。
2. 深入分析在定子磁場導向控制下，全階磁通估測型無感測器理論分析與詳細的推導，接著介紹於靜止座標系下之參考模型適應性系統之降階估測法，最後模擬其兩種不同無感測器之結果與實測波形，探討其優缺點。
3. 發展一套2.2kW三相6極的雙饋式感應發電機系之xPC即時控制發展平台，以驗證本論文控制理論的正確性。

In recent years, doubly-fed induction generators (DFIGs) has become one of the major type of variable-speed fixed-frequency generators for large-scale wind farm applications. Some elementary sensor-based flux-oriented control strategies have been successfully implemented in current wind power industry practice. Similar to technology developments in conventional fixed-speed induction generator, sensorless control may be a new issue to further reduce sensor cost and provide similar satisfactory transient performance of sensor-based control. The main theme of this thesis is to study sensorless control algorithms for DFIGs. Both grid-connected and stand-alone configurations will be addressed. The main contributions of this thesis can be summarized as follows:
Static characteristics of DFIGs and their operating capacity will be conducted first. Dynamical models in terms of both the voltage and current model on stator flux oriented control will be developed in the generalized flux-oriented scheme. And a laboratory real-time control 2.2 kW DFIG platform is developed. The system is constructed by Matlab/Simulink and xPC system. Finally two types of sensorless control, including the model reference adaptive system (MRAS) control and the full-order observer control , are studied. Detailed analysis are provided. Both software simulations and hardware experiments are conducted. Experimental works have been conducted to verify the effectiveness of the proposed control strategy. Comparion studies of both sensorless control laws are also discussed.

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