應用部分放電法診斷電力變壓器絕緣之研究

Application of Partial Discharge Testing to Power Transformer Insulation Diagnosing

林冠文(Kuan-Wen Lin)

指導教授 ： 曾國雄 老師

國立臺北科技大學/電資學院/電機工程系研究所/碩士(2009年)

摘要

隨著電力系統電壓等級逐年提升與環境變化的影響下，使得電力設備上絕緣材料所承受的壓力日益增加，影響設備的絕緣性能，並導致電力設備的故障。本論文提出以部分放電檢測法，應用於發電廠內變壓器之絕緣狀態評估，經由廠內定期執行絕緣油之油中氣體檢查，檢測出所含可燃性氣體含量超過容許值。同時採用超音波感測裝置對故障點定位，判斷其故障點為變壓器的有載切換開關三相連動桿，立即對變壓器停機。將發生故障的連動桿與劣質的絕緣油更新汰換後，於運轉後再次執行油中氣體分析，其絕緣油中氣體含量合於標準值。由研究結果顯示運用油中氣體分析法，並配合部分放電檢測法，對於變壓器故障點位置之判定具有高可靠度，可於運轉中的電力設備，執行絕緣狀態的診斷，避免因檢測時所造成的必要停機，導致電力中斷與經濟損失，擁有較佳預防性維護的參考價值。

關鍵字

部分放電 ； 電力變壓器 ； 油中氣體分析 ； 超音波檢測 ； 預防性診斷

並列摘要

The influence of the power system advances in voltage level and the environmental changes, the higher electrical stress affects the insulation ability of electrical facilities, causing insulation deterioration and electrical failures. This thesis applies a diagnostic method of partial discharge detection method to evaluate the insulation of power transformer in the power plant. Through the plant engineers examine combustible gas from transformer insulation oil periodically. Detection of combustible gas contained was more than the safety allowable value. At the same time, by using the ultrasonic detection device to position the failure location. Determine the failure source from the connection rod of the transformer's on-load tap changer (OLTC), should be shut down the transformer immediately. To replace the failure connection rod and the low quality insulating oil. Then restart normal operation. Finally, using the dissolved gas analysis again to ensure the content of combustible gas is under the safety range. The research result express that apply the dissolve gas analysis and the partial discharge detection method. Could be positioning the failure location inside the transformer and doing insulation evaluating with high reliability because it does without the power supply. For early finding the abnormal phenomenon reduce the power outage and the economic loss. Be taken as reference of the preventive maintenance.

並列關鍵字

Partial Discharge ； Dissolved Gas Analysis ； Ultrasonic Detection ； Power Transformer ； Preventive Diagnostic

參考文獻

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