本文旨在探討運用儲能系統改善電網中的電壓驟降，電壓驟降是電力系統中相當嚴重的電力品質問題，短時間內的電壓下降會影響電網運行，導致資料遺失或設備中斷運作，造成用戶的鉅額損失。因台灣高科技產業發達，對電力系統的穩定性要求極高，特別是半導體製程中有許多敏感性負載，對於電壓波動敏感度較高。為了減緩此問題對電網的影響，本文提出利用儲能系統進行電壓驟降改善，驗證了國際間常見的功率傳輸能力標準應用於改善電壓驟降的性能，評估所需的儲能系統容量。
目前常見的電壓驟降解決方案包括故障電流抑制器、動態電壓調節器以及靜態同步補償器等等，這些設備雖能緩解電壓驟降，但功能較為單一，前兩項僅在電壓驟降時有效，無法兼顧電網正常運作時的其它需求，靜態同步補償器可於電網正常運行時調節虛功，但無法進行實功調控的功能。儲能系統則無上述之缺點，在電網正常與故障期間均具有應用價值，如削峰填谷、契約容量控制以及與間歇性再生能源整合等等。這些功能不僅有助於提高電網的穩定性和韌性，也可與再生能源有效搭配，減少化石燃料的用量，符合聯合國氣候大會推動之2050年淨零碳排的目標。
本文也說明了電壓驟降的定義、原理以及規範，探討了常見的電壓驟降緩解方式與儲能系統的不同之處，於電力系統模擬軟體PSS/E建立2025年輕載、尖載情境之電網系統以及WECC儲能系統通用模型，並以國際間常見之功率傳輸能力要求作為控制策略之參考，補償目標則依據全球半導體產業協會提出之電壓驟降抗擾度規範。當電網之345kV超高壓匯流排發生短路故障導致電壓驟降時，設置於161kV特高壓匯流排之儲能系統可迅速反應，依據控制策略注入虛功以進行電壓支持，並在故障清除後加速電壓恢復至標稱值，最後，評估所需的儲能系統容量以作為未來設置容量之參考，可驗證使用儲能系統於電壓驟降改善具有一定程度的效益。

This thesis aims to explore the application of battery energy storage systems to improve voltage sags in the electrical grid. Voltage sags significantly affect power quality; short-term voltage drops can disrupt grid operations, leading to data loss or equipment shutdowns, resulting in substantial losses for users. Given Taiwan's advanced high-tech industry and its high demands for power system stability, particularly in semiconductor processes where loads are highly sensitive to voltage fluctuations, this paper proposes the use of ESS to mitigate the impact of voltage sags on the grid. It validates the performance of common international power transmission capacity standards for improving voltage sags and assesses the required capacity of energy storage systems.
Current solutions for voltage sags include fault current limiters, dynamic voltage restorers, and static synchronous compensators. Although these devices can alleviate voltage sags, their functionalities are relatively singular; the first two are only effective during voltage sags and do not address other needs during normal grid operations. Static synchronous compensators can adjust reactive power during normal operations but lack real power control capabilities. Energy storage systems do not have these limitations and are valuable during both normal and fault conditions, offering peak shaving, contract capacity control, and integration with intermittent renewable energy sources. These functionalities not only enhance the stability and resilience of the grid but also align with the United Nations Climate Conference's goal of net-zero carbon emissions by 2050 by effectively pairing with renewable energy and reducing fossil fuel usage.
Before conducting simulation analysis, this paper defines voltage sags, their principles, and standards. It discusses common mitigation methods for voltage sags compared to energy storage systems and introduces the WECC generic BESS model. The paper establishes a 2025 light-load and peak-load grid system scenario in the power system simulation software PSS/E, using common international power transmission capacity requirements as a reference for control strategies. The compensation target is based on the voltage sag immunity specifications proposed by the Semiconductor Equipment and Materials International. When a voltage sag occurs at the 345kV ultra-high voltage bus, the BESS located at the 161kV extra-high voltage bus can respond quickly, injecting reactive power according to the control strategy to support the voltage, and accelerate the voltage recovery to the nominal value after fault clearance. Finally, the paper assesses the required capacity of the energy storage system to serve as a reference for future capacity installations.

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