環氧樹脂由於良好的電絕緣特性常用於變壓器、絕緣套管等高壓設備絕緣，然而，製造上的瑕疵將會造成不可預期的事故，為此透過量測局部放電判斷設備絕緣狀態是個重要的議題。
本研究以針尖－平面電極結構來實驗環氧樹脂生成電樹的劣化現象，同時量測並記錄過程中產生的局部放電訊號，並將其帶入既有的壽命診斷系統。實驗被試物以透明色環氧樹脂製作以方便觀察變化，製作針尖－平面間距為1cm與1.5cm的實驗樣本各5組，利用總放大倍率2倍的放大鏡放大畫面並以縮時攝影機記錄實驗樣本變化。
實驗結果發現環氧樹脂緣劣化過程的電樹現象可分為初始深色電樹、絲狀電樹、逆向電樹、絕緣破壞幾個階段，並對各階段電樹完成簡易的觀察。經由將放電訊號代入壽命診斷系統可以發現大部分樣本在試驗的中期可辨識成注意期，並在中後期開始可辨識成危險期。對比發現注意期訊號與攝影畫面暫無明顯關聯，危險期訊號則可觀察到較大且較頻繁的放電，導致被試物溫度上升而發生形變。

Epoxy resin is widely used in the insulation of high-voltage equipment such as transformers and insulating bushings due to its good electrical insulation properties. However, manufacturing defects will cause unpredictable accidents. Therefore, it is an important issue to determine the insulation state of equipment by measuring partial discharges.
In this study, the needle-plane electrode structure was used to test the epoxy resin electrical treeing insulation deterioration phenomenon. During the test, we measured partial discharge signal, and then used the signal as the input data of the insulation status assessment system which developed in the past research. The experimental samples were made of transparent epoxy resin to facilitate the observation of changes, and were made in the distance of 1cm and 1.5cm of 5 sets. During the experiment, a magnifying glass with a total magnification of 2 times is set up to enlarge the picture and a time-lapse camera is used to record the changes of the experimental samples.
In the experiment, we found that the electrical treeing phenomenon of epoxy resin insulation deterioration process can be divided into several stages: initial dark tree, filamentary tree, reverse tree and insulation breakdown, and simply observed each stage of electrical treeing. After substituted the partial discharge signal into the insulation status assessment system, it can be found that most experimental samples assessed into attention period in the middle of the test, and into the risky period in the middle and late of the test. Compared the attention period signal to the recorded film, there was no obvious correlation currently, but compared to the risky period signal can see that the experimental sample deformed due to the temperature rise caused by larger and more frequently discharge.

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