本論文經由智慧型電子裝置之輔助，探討變壓器湧入電流之保護及抑制，此乃因湧入電流可能高達數倍之額定電流，且可能持續數百毫秒，因此可能影響保護電驛之判別準確度，確有必要針對此現象予以探討及提出抑制或防治對策。幸拜賜於智慧型電子裝置具有高彈性之程式規劃能力，因此本論文將其應用於降低湧入電流對電力設備之衝擊，同時完成更具可靠度之放射型饋電系統之保護協調。又為使本文所提之方法確實有施行參考價值，本文實作變壓器之加壓測試，並分析量測變壓器湧入電流現象，且整合利用智慧型電子裝置之可程式邏輯功能，以有效掌握過電流電驛之保護功能，進而降低相關連接設備之損壞機率，俾以確保高品質之供電系統。

This thesis investigates the application of intelligent electronic device to suppress the inrush current of transformer. This study is motivated because the magnitude of inrush current is often several times higher than that of rating current of transformers, by which the performance of protection relays is often affected. Thanks to high flexibility of programming function of intelligent electronic device, it is applied to reduce the impact of transformer inrush current. Meanwhile, the protection coordination of radial distribution system would become more reliable. To ensure the practical value of this proposed strategy, the method has been validated with transformer tests by measuring the resulted current waveforms. It is anticipated that these results can decrease the probability of equipment damage, thereby ensuring a high-quality power-supplying system.

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