研究旨在探討介質損耗角量測應用於灌膠製程環氧樹脂乾固品質評估之可行性，並與局部放電（PD）量測結果進行比較分析。局部放電量測可有效反映材料內部缺陷，而介質損耗角量測則可藉由材料介電特性變化評估其乾固狀態與絕緣品質。
研究以一般環境灌膠與真空灌膠兩種製程條件製備環氧樹脂試片，分別進行局部放電與介質損耗角量測。結果顯示，真空灌膠試片具有較低之局部放電幅值，且介電指標（DI）多呈負值；相較之下，一般環境灌膠試片之局部放電幅值較高，且 DI 值多呈正值，顯示其介電損耗與放電風險較高。
綜合分析結果可知，介質損耗角量測所建立之 DI 指標與局部放電量測結果呈現一致之品質判別趨勢，能有效區分不同灌膠製程下之乾固品質差異。研究結果顯示，介質損耗角量測與局部放電量測皆具有良好的品質辨識能力，可依不同檢測需求與應用情境作為環氧樹脂灌膠品質評估之工具。

This study investigates the feasibility of using dielectric loss tangent measurements to evaluate the curing quality of epoxy resin in potting processes and compares the results with partial discharge (PD) measurements. PD measurements are commonly used to detect internal insulation defects, whereas dielectric loss tangent measurements evaluate insulation quality through changes in dielectric properties.
Epoxy resin specimens were prepared using atmospheric potting and vacuum potting processes. The results showed that vacuum-potted specimens exhibited lower PD amplitudes and lower dielectric degradation index (DI) values, indicating better insulation quality. In contrast, atmospheric-potted specimens exhibited higher PD amplitudes and higher DI values, suggesting greater dielectric loss and discharge risk.
The results demonstrate that the DI index derived from dielectric loss tangent measurements shows a quality assessment trend consistent with PD measurements and can effectively distinguish curing quality differences between potting processes. Therefore, both dielectric loss tangent and PD measurements can serve as effective methods for evaluating the curing quality of epoxy resin under different testing requirements and application scenarios.

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