基于Friis传输方程的局部放电定量计算方法研究

Calculation model of the discharge capacity based on Friis transmission equation

特高频法监测电缆及GIS局部放电时需要对放电量进行精确地标定,以判断局部放电严重程度。文中提出一种利用Friis传输方程对局部放电定量计算的方法,该方法将局部放电源作为发射天线模型化处理,并引入Friis传输方程,将计算等效为天线传输过程,应用HFSS仿真得到的四阶Hilbert分形天线作为接收天线模型。通过局部放电试验与计算分析验证,确定了局部放电量与接收特高频信号的能量呈二次曲线的关系。

In order to determine the severity of partial discharge,precise calibration in the amount of discharge is required for the application of ultra-high frequency in cable and GIS partial discharge monitoring. In this paper,a method for the calculation of partial discharge based on Friis transmission equation is presented,which integrates partial discharge source as a transmitting antenna modeling and introduces Friis transmission equation to make the calculation equivalent to the transmission process of the antenna. By taking the fourth-order Hilbert fractal antenna resulting from HFSS simulation as receiving antenna model,and utilizing partial discharge tests,calculation and analysis,the quadratic curve relationship between partial discharge and the energy of receiving UHF signals is determined.