Acta Scientiarum Naturalium Universitatis Pekinensis ›› 2019, Vol. 55 ›› Issue (5): 865-870.DOI: 10.13209/j.0479-8023.2019.068

Previous Articles     Next Articles

Research on Transformer Oil Aging by Nuclear Magnetic Resonance Spectroscopy of Relaxation Time

LI Xiaonan1, LIU Guoqiang1,2,†, ZHANG Laifu3, WANG Zhipeng3, DING Guangxin1, ZHAO Shilong1,4, XIA Hui1   

  1. 1. Research Department of Electromagnetic Field and Applied Technology, Engineering Institute of the Chinese Academy of Sciences, Beijing 100190 2. University of Chinese Academy of Sciences, Beijing 100049 3. Research Institute of Electric Power Science, Shanxi Electric Power Company, Taiyuan 030001 4. School of Electrical Engineering, Hebei University of Technology, Tianjin 300401
  • Received:2018-10-29 Revised:2019-01-11 Online:2019-09-20 Published:2019-09-20
  • Contact: LIU Guoqiang, E-mail: liuguoqiang(at)mail.iee.ac.cn

基于核磁共振弛豫谱的变压器油老化检测研究

李晓南1, 刘国强1,2,†, 张来福3, 王志鹏3, 丁广鑫1, 赵世龙1,4, 夏慧1   

  1. 1. 中国科学院电工研究所工程电磁场及应用技术研究部, 北京 100190 2. 中国科学院大学, 北京 100049 3. 国网山西省电力公司电力科学研究院,太原 030001 4. 河北工业大学电气工程学院, 天津 300401
  • 通讯作者: 刘国强, E-mail: liuguoqiang(at)mail.iee.ac.cn
  • 基金资助:
    北京市自然科学基金(7182111)和国家自然科学基金(51577184)资助

PDF

Abstract:

According to the limitations of conventional thermal aging detection of transformer oil insulation (not accurate or complicated process), a low field nuclear magnetic resonance relaxation time spectrum detection method is proposed. Based on the principle that hydrocarbon compounds in oil are cracked in high-pressure discharge environment and the molecular structure of hydrogen-containing molecules is changed, a transverse NMR relaxation spectrum detection system for thermal aging of transformer oil is designed. An algorithm for obtaining relaxation time spectrum based on inversion is described by using the peak point of time domain signal of oil samples collected by spin echo sequence. With the oil samples from the 110 kV power station in Changzhi City, the aging factor was detected by the nuclear magnetic resonance relaxation spectroscopy. The oil samples were used for 1, 10 and 20 year, individually. The results show that, in a 17.173 MHz condition, the relaxation time is 203.83, 145.82 and 141.95 ms, respectively. The detection time is controlled within 1 minute. The decreasing trend of relaxation time indicates that the high temperature causes the breaking of molecular chemical bonds and the precipitation of small hydrocarbon gases.

Key words: nuclear magnetic resonance, relaxation spectroscopy, pulse sequence of spin echo train, transformer oil, thermal aging

摘要：

针对目前常规的变压器油绝缘热老化检测中过程繁杂等问题, 提出一种基于低场核磁共振弛豫时间谱的检测方法。根据油品中烃类化合物在高压放电环境中出现裂解、结构发生改变的原理, 设计变压器油热老化核磁共振横向弛豫谱检测系统。采用自旋回波序列采集油样时域信号回波峰值点, 描述弛豫时间谱反演算法。利用山西省电力公司长治变电站110 kV高压变压器提取的油样(挂网运行年限分别为1, 10和20年), 进行检测装置性能的验证及测试。结果表明, 在17.173 MHz条件下, 该检测方法可以在1分钟内完成一次油样的信号检测与弛豫谱反演, 3种油样的弛豫时间峰值分别为203.83, 145.82和141.95 ms。可以看出, 随着年限的增加, 弛豫时间呈下降的趋势, 表明高温能够导致油品中分子化学键断裂, 析出气体。

关键词: 核磁共振, 弛豫时间谱, 自旋回波序列, 变压器油, 热老化

Copyright © Acta Scientiarum Naturalium Universitatis Pekinensis, All Rights Reserved.
Powered by Beijing Magtech Co., Ltd.