| 引用本文: | 王涛,黄跃华,贺景良,王勇,魏建军,徐阳.抗干扰技术在电力变压器局部放电在线监测中应用[J].电力自动化设备,2007,27(2):104-107 |
| .Application of anti-interference techniques to on-line partial discharge monitoring of power transformer[J].Electric Power Automation Equipment,2007,27(2):104-107 |
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| 摘要: |
| 针对电力变压器现场干扰信号特点,采用了软件辅助的脉冲定向耦合法进行抑制,即利用每相高压套管底座和套管末屏接地线上的2个磁芯式电流传感器耦合信号,通过软件鉴别2路传感器所耦合到的脉冲信号第1个峰值的极性,判断2路传感器脉冲极性的异同,从而定向耦合变压器内部的放电脉冲,可有效去除随机脉冲型干扰;同时将动态阈值、数字滤波及相位开窗等抗干扰技术融合到在线监测系统中,综合去除背景噪声、固定频段干扰、周期性脉冲等,使监测数据真实可靠.通过在220 kV变电站的实践应用验证了系统监测的有效性及可靠性. |
| 关键词: 电力变压器 局部放电 抗干扰 脉冲极性鉴别 |
| DOI： |
| 分类号:TM41 |
| 基金项目: |
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| Application of anti-interference techniques to on-line partial discharge monitoring of power transformer |
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WANG Tao HUANG Yue-hua HE Jing-liang WANG Yong WEI Jian-jun XU Yang
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| Abstract: |
| According to field interference characteristics of power transformer,the directional coupling method with software aided is used to suppress pulse shaped interferences. Pulse signals are coupled by two magnetic core current sensors respectively installed near the flange of the HV bushing and near the capacitance tap to earth per phase,then sent to a computer after amplification. A software program is used to identify the polarity of the head wave for every pulse signal from each sensor,and then distinguish noise from true partial discharge signal by their different pulse polarities. Different anti- interference techniques,such as dynamic threshold,digital filter and phase windows,are used in the monitoring system to remove background noise,fixed band interferences and periodic pulses to make the monitored data real and reliable. The effectiveness and reliability of the monitoring system is validated by its practice in a 220 kV substation. |
| Key words: power transformer partial discharge anti- interference pulse polarity discrimination |
