开关柜局部放电检测技术的应用研究

Application Study on Detection Technology of Switchgear Partial Discharge

i在商用实体开关柜中对典型局部放电源的放电特征进行了分析研究。综合应用暂态对地电压（TEV）和超声波技术对高压开关柜典型缺陷的局部放电进行了检测与分析．对TEV和超声波法检测典型局部放电源有效性进行了综合分析。实验结果表明，不同典型缺陷的放电脉冲相位分布图各有其特征。放电能量不同，同一典型缺陷放电脉冲相位分布图也不尽相同。超声波法检测到信号频谱主要集中在40kHz附近，放电越剧烈，出现倍频成分。超声波检测法对绝缘空穴放电的有效性差。TEV法检测到的信号的频谱主要集中在3～80MHz之间，高频分量（150MHz以上）较少。不同缺陷类型TEV检测信号的频谱存有差异，悬浮电极缺陷的频谱分量丰富。

The discharge characteristics of typical partial discharge source were analyzed for commercial switchgear. Transient Earth Voltage （TEV）and ultrasonic Partial Discharge（PD）detection technology were used to detect and analysis on the typical partial discharge source, and integrated compliance tested effectiveness of（TEV） and ultrasonic PD detection technology. Experimental results showed that different typical defects of discharge pulse have different phase distribution characteristics. The same typical defects of discharge pulse have different phase distribution characteristics with the different discharge energy. Ultrasonic detected signal spectrum was mainly concentrated in the fundamental and harmonic components of 40 kHz due to the sensor frequency range, and the discharge more intense, the more harmonic component frequency. For insulation cavity discharge, the effectiveness of ultrasonic detection was poor. Ultrasonic detected signal spectrum was mainly concentrated between 3-80 MHz, high frequency component was less（above 150 MHz）. The spectrum of TEV detection partial discharge sources were different, and there were a large number of spectrum component in suspended electrode defect .