毫微秒脉冲法用于变压器绕组变形研究初探

Study on the Nanosecond Pulse Method of Detecting Winding Deformation of Power Transformer

变压器绕组变形是变压器的常见故障,为提高变压器绕组变形检测的灵敏度,对毫微秒脉冲检测法进行了研究。着重对毫微秒脉冲参数的选择进行了探讨,通过仿真计算选择了波前5ns30%,脉冲宽度为50ns30%的脉冲作为脉冲信号。利用毫微秒脉冲法对试验变压器进行了绕组变形检测,试验结果证实该方法能较好反应出绕组变形,同时,在0～80MHz范围内试验结果的重复性较好。

Winding deformation is one of the most common faults of power transformers.It may cause partial discharge,even leads to insulation breakdown.Winding deformation also may cause the declining of mechanical properties of winding.The study of high sensitive detection method has important significance in detecting minimal change of transformer winding.This article proposes utilizing the nanosecond pulse method to detect winding deformation.How to select the parameters of the nanosecond pulse is studied emphatically.Through computer simulations,an impulse that has a wave front 5ns±30% and impulse width 50ns±30% is regarded as the ideal signal source.A testing power transformer was detected by the way with the nanosecond pulse.Testing results reflect winding deformation very well.At the same time,the repeatability is good in the frequency range from 0 to 80MHz.