环氧树脂针-板缺陷在指数衰减脉冲和正弦电压作用下的局部放电特性

Partial Discharge Characteristics of Epoxy Resin Needle-Plate Defect under Exponential Decay Pulse and Sinusoidal Voltage

制作了环氧树脂针-板缺陷,模拟饱和电抗器环氧树脂内部金属突出物缺陷,研究环氧树脂在指数衰减脉冲电压和正弦电压下的局部放电特性。从起始放电电压、放电次数、平均放电幅值和局部放电的统计分布特性等方面进行对比,同时分析了环氧树脂样品在25℃和110℃下的局部放电特性。研究发现,在同样峰值的正弦电压和指数衰减脉冲电压下,脉冲电压下的起始放电电压更低,平均放电幅值更大,放电次数更少;对于相同的外施电压,110℃下的起始放电电压较25℃下的更低,平均放电幅值更大,放电次数减少。实验结果可为在指数衰减脉冲电压下饱和电抗器绝缘的优化设计提供依据。

Epoxy needle-plate defects were fabricated to simulate the defects of metal protrusions in the epoxy resin of the saturable reactor in this paper.The partial discharge(PD)characteristics of epoxy resin under exponential decay pulse voltage and sinusoidal voltage were studied.The comparison and analysis were conducted from the aspects of PD inception voltage,PD number,average PD magnitude and PD distribution.The PD characteristics at 25℃and 110℃were also compared and analyzed in this paper.It is found that under the same amplitude exponential decay pulse voltage and sinusoidal voltage,the PD inception voltage under the pulse voltage is lower,PD magnitude is larger and PD number is smaller.For the same applied voltage,the PD inception voltage at 110℃is lower than that at 25℃,the average PD magnitude is greater,and the PD number is reduced.The experimental results can provide a basis for optimal insulation design of saturable reactor under exponential decay pulse voltage.