隨著天然能源日漸匱乏以及環境污染日益嚴重，風力發電正在全球高速發展，各國視之為解決溫室效應的良方。而雙饋式感應發電機由於其具有變速恆頻與高轉換效率等優點，使得其成為風力發電技術的重要發展方向。雙饋式感應發電機透過激磁控制策略，可以實現於轉速變化下的穩定運轉，以及發電機輸出的實功與虛功功率。同樣的，其建構的成本也納入考量，目前的技術大多依賴轉速感測器；因此無感測器控制為一節省成本的良方，且近似於系統基於轉速感測器作控制時的暫態表現。
因此本文將深入探討兩種參考模型適應性系統的無感測器理論，並應用於雙饋式感應發電機系統。
首先，敘述雙饋式感應發電機系統的架構與固態轉換特性；其次，分別建立電網側轉換器動態模型與轉子側轉換器動態模型，進而推導出電網側轉換器的直流鏈電壓控制與轉子側轉換器的實功功率控制以及虛功功率控制。接著本文提出兩種無感測器控制，分別為反電動勢模式參考適應型轉速估測器控制與瞬時虛功模式參考適應型轉速估測器控制，並以MATLAB/Simulink模擬兩控制法於DFIG系統。最後以一基於MATLAB/Simulink的xPC 系統來即時控制一套2.2kW的雙饋式感應發電機硬體平台，將反電動勢模式參考適應型轉速估測器控制利用於此，並以實測波形的呈現來證明其可行性。

With the situation of energy source exhaustion and environmental pollution, the wind energy generation is gaining more and more attention around the world. It is now recognized that many large farms will employ doubly fed induction generator (DFIG) variable speed wind turbines. Hence, some elementary sensor-based flux-oriented control strategies have been successfully implemented in current wind power industry practice. Also, it is very important to reduce cost. Sensorless control might be a good way to save the cost of sensor and provide similar satisfactory transient performance of sensor-based control.
The main theme of this thesis will study a model reference adaptive system (MRAS) for a speed sensorless control of the vector controlled DFIG system. The main contributions of this thesis can be summarized as follows:
First, conducting the Static characteristics of DFIGs and their operating capacity. Second, the dynamic model of grid side converter and rotor side converter will be constructed, respectively. According to those models, the dc-link control for grid side converter and the active/reactive control for rotor side converter can be shown. Third, we propose two sensorless controls, including the Back-emf model reference adaptive system control and the Instantaneous-reactive power model reference adaptive system control, are studied. Also, we simulate those two sensorless controls by Matlab/Simulink. Finally, a xPC system which is constructed by Matlab/Simulink control a 2.2 kW DFIG hardware platform in real time. The Back-emf model reference adaptive system control will be use in the DFIG system. We will show the measured waveforms to demonstrate the performances of the proposed sensorless controls.

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