於高科技產業或是傳統工業中，穩定的電力供應向為不可或缺的要件，而由於變壓器往往是廠區電力供應之樞紐，因此對於變壓器之保護，更需縝密設計，但由於變壓器之鐵心特性，當變壓器之電源開關由切離電源的狀態再投入電源時，常會產生湧入電流現象，導致保護電驛誤動作發生，因此本論文即經由場規劃邏輯閘陣列(Field Programmable Gates Array, FPGA)實現小波轉換，並將其應用於變壓器湧入電流之鑑別，亦即將小波轉換分析暫態訊號之時頻定位能力與多重解析的特性，硬體實現於場規劃邏輯閘陣列之中，並結合原有之保護電驛，提供變壓器更可靠之保護機制。為驗證本方法之可行性，文中並以模擬訊號與實測訊號分別測試，測試結果佐證本論文之實際應用價值。

　　For the high-tech or traditional industry, the stable power supply is always a very critical requirement, where the transformer is deemed a supply hub for the supplying power. It is also hence commonly recognized that the transformer protection should be prudently designed. However, because of nonlinear characteristics of tansformer coils, it often lead to the scenario of huge amount of inrush current once the power source is switched on, thereby even causing the misoperation of protective relays. In view of such drawbacks, this thesis is, therefore, aimed at the identification of transformer inrush current through the wavelet transform aided with the field programmable gate array. In other words, the time-frequency localization and multi-resolution capabilities of wavelet transform are both employed to distinguish the occurrence of inrush current, where the hardware realization is also accomplished. To validate the effectiveness of this proposed scheme, the approach was also individually tested through the simulation signals and experimental data. The test results confirm the practical values of the proposed method.

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