GIS局部放电超高频检测法有关问题的仿真研究

气体绝缘组合电器(gas insulated switchgear,GIS)中的局部放电在腔体中产生超高频(ultra high frequency,UHF)电磁波信号。为研究GIS局部放电源与UHF信号的关系,利用时域有限差分法计算局部放电产生的UHF信号;通过改变放电源和探头的参数,研究了局部放电产生的UHF信号的特性。仿真分析结果表明:UHF信号的幅值与局部放电脉冲幅值成线性关系;UHF信号与放电源的径向位置、放电通道长度、放电脉冲波形以及放电源与探头的夹角有关。单纯 UHF信号很难解释局部放电量的大小,但UHF信号可在一定程度上反映出GIS的绝缘状态。

Research on Ultra-High-Frequency Method for Detection of Partial Discharge in GIS

In gas insulated switchgear (GIS) the partial discharge (PD) causes ultra high frequency (UHF) electromagnetic wave signals within the switchgear body. To research the relation between the PD source and UHF signals, the PD caused UHF signals are calculated by finite difference method in time domain; by means of changing the parameters of PD source and sensors, the characteristics of UHF signals caused by PD are researched. Simulation results show that the amplitudes of UHF signals are in linear relation to those of PD pulses; the UHF signals relate to following factors: radial position of PD source, length of discharging channel, waveform of discharging pulse and the included angle between the PD source and sensor. It is hard to explain the discharge quantity merely by UHF signals, however the UHF signals can reflect the insulation situation within the GIS to a certain extent.