电容探头法测量绝缘子表面电荷的标度算法

气体绝缘开关装置中,表面电荷积聚会降低绝缘子的沿面闪络电压。为了改善气体绝缘开关装置的绝缘设计,需要对绝缘子表面电荷分布进行准确测量。采用传统的标度方法无法准确的求得绝缘子表面电荷密度。目前可能的解决办法有两种:①结合电场数值计算理论进行多点标度;②采用二维傅立叶变换及数字图像处理技术来解决该问题。通过对两种标度算法的综述及分析比较,认为第①种标度算法可以实现对任意结构的绝缘子表面电荷分布进行标度,但存在标度耗时过长的缺点;而第②种标度算法可以极大地缩短标度计算耗时,但其应用条件比较苛刻。但相对于传统的标度方法,这两种标度方法能较为准确的求出绝缘子表面电荷的分布。

Calibration of Capacitive Probe Measurement for Insulator Surface Charge

In gas insulated switchgear (GIS), the flashover voltage of insulator can be reduced by the influence of surface charge accumulation. In order to improve the insulation performance of GIS, it is necessary to measure the surface charge distribution accurately. Accurate information of the accumulated charge distribution based on traditional calibration method is hard to obtain. Two calibration methods were presented recently, one is based on electromagnetic computation theory, and the other is based on Fourier transform method and digital image processing technique. Trough comparison and analysis, it can be seen that though the first calibration method can be used for any structures of insulator, the calibration time took by the first method is very long, and for the second calibration method, though the calibration time is saved much, the application of the second method is limited by some rigor conditions. Compared with the traditional method, the two methods can used to obtain accurate surface charge distributions relatively.