分散式發電系統獨立運轉現象係指分散式發電機與市電併聯供電時，可能發生分散式發電機與市電解聯現象，導致發電機與負載形成單獨供電之微型電網。而當發生此類發電機獨立運轉現象時，若工程人員無法掌握目前供電來源，即有可能誤判，甚且導致電力設備故障及影響運轉安全。有鑑於此，本文應用小波能量熵於分散式發電系統獨立運轉之偵測，其中所提方法主係經由小波能量熵對於訊號之量化程度，進而掌握電壓頻率之能量分布，同時經由差分小波能量熵之計算，進而判斷是否發生分散式發電系統獨立運轉，並據以協助提升無法偵測區之鑑別機率。而為驗證本文方法之可行性，本文經由數值模擬及應用演算法分析探討分散式發電系統獨立運轉模型架構，並輔以場規劃邏輯閘陣列晶片予以硬體實現驗證，測試結果應可協助佐證本文所提方法於分散式發電系統獨立運轉偵測效能之增進。

The islanding operation of distributed generation systems happens when the distributed generators are disconnected from the mains power such that the load is purely supplied by those connected distributed generators. Under such scenarios, if the occurred event is not informed in time, it may damage the electric power equipment and affect the safety of operation personnel. In view of this importance, the thesis has devoted to the study of islanding operation detection via the wavelet energy entropy method. It is found that by employing the proposed method, it would help quantify the waveform such that energy distribution of voltage as well as frequency is better grasped, thus assisting the forewarning of the occurrence of islanding events. To confirm the feasibility of the method, the simulated model has been tested by the proposed approach and FPGA validation. Test results help support the method for the islanding detection enhancement of distributed generation systems.

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