微電網是智慧型電網之一環，可運轉於併網模式與孤島模式，而孤島運轉又區分為有目的性孤島與意外性孤島，微電網之孤島模式即為有目的性孤島。而意外性孤島運轉係指市電系統因為發生故障而電源跳脫，導致分散式電源與其區域負載形成孤島運轉區域系統，若分散式電源不具備穩定系統電壓與頻率調整的能力，則可能會導致負載設備的損壞。此外，為保護市電系統維修人員的工作安全，分散式電源應儘速與區域系統隔離，因此分散式電源須具備孤島檢測功能，在發生意外性孤島運轉後必須將其解聯。同理，運轉在併網模式的微電網，當市電系統發生故障時，基於安全理由可將其可切換至孤島模式，亦即微電網內之分散式電源可維持持續運轉，這全仰賴微電網併網點的孤島檢測技術與功能。然而此併網點的孤島檢測技術與分散式電源本身的孤島檢測技術存在本質上的差異，無法等同視之。因此對於微電網內部之分散式電源，不同的意外性孤島運轉範圍，會有持續運轉與跳脫兩種選擇，傳統的孤島檢測技術也不再適用於微電網內部之分散式電源。
本論文提出整合SCADA、IED與MU的微電網孤島檢測系統，並以IEC 61850標準當作檢測系統之通訊協定。對於不同的孤島檢測對象，本文提出兩種孤島檢測技術，首先以間次諧波電流注入法作為微電網之併網點孤島檢測技術，而對微電網內部之分散式電源，則以IED間的GOOSE通訊進行孤島檢測。最後以Matlab/Simulink建置微電網範例系統，驗證本文提出之微電網孤島檢測系統之可靠性，模擬結果證實孤島檢測系統對於可以有效地偵測意外性孤島運轉，並對於非孤島事件不會發生誤動作。

Microgrid is a part of smart grid, which can be operated in grid-connected mode and islanding mode. The islanding is divided into intentional islanding and unintentional islanding, and the islanding mode of microgrid belongs to the intentional islanding. The unintentional islanding means that the utility fails, causing the distributed generation and neighboring load to form an island. If the distributed power supply does not have the ability to stabilize the system voltage and frequency, it may cause damage to the load equipment. In addition, in order to protect the safety of maintenance personnel, the distributed generation should be isolated from the island immediately. Therefore, the distributed generation must have an islanding detection function. Similarly, the microgrid operating in grid-connected mode can be switched to islanding mode for safety reasons when the utility fails. Consequently, the distributed generation in the microgrid can continue to operate, which depends on the islanding detection function at PCC of the microgrid. However, there is a difference between the islanding detection for the PCC of the microgrid and the islanding detection for the distributed generation. In addition, the traditional islanding detection technology is no longer applicable to the distributed generation in the microgrid.
This thesis proposes a microgrid islanding detection system integrating SCADA, IED and MU. The IEC 61850 standard is used as the communication protocol of the detection system. There are two islanding detection methods, namely the inter-harmonic current injection method and the GOOSE communication method are introduced to run in different islanding areas. Finally, an example microgrid system has been set up by Matlab/Simulink to verify the reliability of the proposed method. The simulation results shows that the proposed method work perfectively both in unintentional islanding detection and non-islanding events of microgrid.

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