溫度及溼度對25kV XLPE電纜 絕緣特性之影響

The Influence of Temperature and Moisture on the Insulation Characteristics of 25kV XLPE Cable

陳國光(Kuo-Kuang Chen)

指導教授 ： 何金滿 ； 周至如

中原大學/工學院/電機工程研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700244

摘要

本文主要對電纜及其附件結構功能做介紹，並對可能影響絕緣材料老化的環境因子、老化機制及效應做探討，研究目的主要為運用局部放電(Partial Discharge)檢測技術，並搭配絕緣電阻及介電損失檢測，應用於電纜及其終端接頭於設定環境應力下絕緣狀態的檢測，期能早期發現電纜老化跡象，達到預測性診斷之目的。
研究方法係藉由恆溫恆濕試驗機及自耦變壓器分別對12條25kV XLPE電纜進行二項環境驗證，第一項為溫度與濕度合成效應環境驗證，第二項為在15kV定電壓下，300A電流定時啟起閉環境驗證，於環境驗證過程中對電纜進行局部放電、介電損失及絕緣電阻檢測，以瞭解此三種檢測方法對電纜內部瑕疵的辨識能力，找出適宜的診斷方法。
依據測試數據整理及分析結果，可知局部放電、絕緣電阻及介電損失等三種檢測方法，在上述二種環境下，對電纜內部瑕疵的判定，依序為局部放電檢測具有較佳的辨識能力，但易受雜訊干擾，絕緣電阻檢測的辨識能力最差，介電損失檢測則可適用於潮濕環境電纜檢測，並可結合局部放電檢測，以得知電纜整體絕緣狀態及內部瑕疵之劣化程度。

關鍵字

環境應力 ； 局部放電 ； 老化效應 ； 老化機制

並列摘要

This report introduces the structure and function of cable and accessories. In addition, this report also deals with potential environmental factors, aging mechanisms and effects resulting in insulation degradation of cables. The prime purpose is to use partial discharge (PD) measurement combining with insulation resistance measurement and dielectric loss measurement to detect the insulation status of cables and terminals under environmental stresses, to early find the aging indications of cables, and further to reach the purpose of predictive diagnosis.
The method is to utilize a programmable temp. & humi. chamber and autotransformers to carry out two kinds of environmental qualification on twelve samples of 25kV XLPE cables. One is a synergistic experiment of temperarure and moisture. Another environment is in a constant ac voltage of 15kV rms with a 300A current switching regularly. In the process of environmental experiment, appling PD measurement, insulation resistance measurement and dielectric loss measurement to know the recognizition ability on internal defects of cables and to find the diagnostic methods available.
The experimental results show among the PD measurement, insulation resistance measurement and dielectric loss measurement, PD measurement seems to have better performance to recognize internal defects of cables, but it’s easy to be disturbed by noise. Insulation resistance measurement has worst performance in internal defects detection. Dielectric loss measurement can combine with PD measurement applied in a wet environment to obtain the integral insulation states and internal defects of cables

並列關鍵字

environmental factor ； aging effect ； partial discharge ； aging mechanism

參考文獻

位技術報告，私立中原大學電機工程學系，2003年。

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