為配合國際再生能源發展之趨勢，我國訂定了能源轉型政策，規劃2025 年再生能源發電佔比達20 %之政策目標。然而再生能源發電易受環境因素影響且其主要透過電力電子轉換器與系統併網。當再生能源發電佔比過高時，其發電不穩定將影響系統之供電可靠度。增設具備輔助服務功能的儲能系統(ESS)可有效用來提高系統供電可靠度及系統頻率穩定度，ESS之輔助服務功能主要包括：頻率控制、電壓穩定與虛擬慣量之提供等。
本論文提出具備虛擬慣量控制技術之ESS結合主動式濾波器，實現：(1)微電網運轉於併網模式時，應用瞬時功率理論執行頻率控制與電壓穩定之輔助服務，完成不同條件下之補償，並考慮ESS之有限輸出容量，加入動態電力品質補償策略，決定無效功率、不平衡與諧波之補償優先順序，以提高ESS之使用效率；(2)微電網運轉於孤島模式時，應用虛擬慣量技術，以增加電力系統之頻率穩定性。最後以Matlab/Simulink建立儲能系統架構，於不同模擬情境下驗證ESS輸出成效。模擬結果顯示，微電網運轉於併網模式時，ESS可提高其使用效率；微電網運轉於孤島模式時，ESS可提供虛擬慣量以維持微電網之頻率穩定。

In order to comply with the development trend of the world’s renewable energy, my country has formulated an energy transition policy, and plans that the proportion of renewable energy power generation in 2025 must reach the policy target of 20% of the total power generation. However, renewable power generation is susceptible to environmental factors and is mainly connected to the power grid through power converters. When the proportion of renewable power generation is too high, its power generation instability will affect the reliability of the power grid. The addition of an energy storage system (ESS) with auxiliary service functions can be effectively used to improve the reliability and the frequency stability of the power grid. ESS auxiliary service functions mainly include: frequency control, voltage stabilization, and provision of virtual inertia.
This thesis proposes an ESS with virtual inertia control technology combined with active filters. The proposed technology can realize (1) When the microgrid is operating in grid-connected mode, the instantaneous power theory is applied to perform auxiliary services of frequency control and voltage stabilization for completing compensation under different conditions. In addition, considering the limited output capacity of the ESS, a dynamic power quality compensation strategy is added to determine the priority order of the compensation for reactive power, unbalance and harmonics, so as to improve the efficiency of the ESS. (2) When the microgrid operates in island mode, the virtual inertia technology is applied to increase the frequency stability of the power grid. Finally, MATLAB/Simulink was used to establish the ESS framework to verify the output effect of the ESS under different simulation scenarios. Simulation results show that when the microgrid operates in grid-connected mode, the ESS can improve its efficiency. When the microgrid operates in island mode, the ESS can provide a virtual inertia to maintain the frequency of the microgrid.

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