电位法绝缘子污秽放电检测的试验研究

为了研究绝缘子放电时观测点电位的基本变化特性,采用等值盐密法,均匀染污试验绝缘子,匀速升高电压,用示波器测量观测点的感应电位信号。在实验室做了一系列绝缘子污秽放电试验,研究了观测点电位信号的污秽特性、交流电压特性和时间特性。试验发现:污秽放电时观测点的电位波形是一系列的电脉冲信号,单脉冲信号的宽度是纳秒级的,主频分布在7kHz和27.5 kHz附近;随试验电压的升高电脉冲信号幅值增大,数目增多,并出现典型的工频周期性;在同一污秽度下,当试验电压不变时,检测到的电脉冲随时间振荡;电位法检测的灵敏度较高,受测点位置的影响较少。

Experiments of Detection of Discharg On Polluted Insulators Using Electric Potential Method

To reveal the primitive electrical potential pattern at observing point when discharging.The inductive potential signal at observing point was measure with oscillograph under steady raised voltage,applied to even contaminated insulator.At a series discharge test on contaminated insulator,conducted in laboratory,characteristics of pollution,discharge voltage and duration at observing point were determined.It is discovered that the potential wave at observing point is a series of electric pulses of nano second,with main frequency located at 7 kHz and 27.5 kHz.Along with rise of test voltage the pulse signals have enhanced amplitude,increased number and perioclicity power frequency.At the same pollution severity and test voltage,the detected pulses oscillate with time.The potential test method has a higher sensitivity and mere effected by test spot.