局部放电(partialdischarge,PD)诊断与定位有助于在老化早期发现高压电力设备故障位置,对制定检修方案具有重要参考价值。目前常利用多个特高频(ultra high frequency,UHF)传感器组成传感器阵列,并定义三维坐标系对变压器进行局部放电...局部放电(partialdischarge,PD)诊断与定位有助于在老化早期发现高压电力设备故障位置,对制定检修方案具有重要参考价值。目前常利用多个特高频(ultra high frequency,UHF)传感器组成传感器阵列,并定义三维坐标系对变压器进行局部放电空间定位。该文研究基于能量积累法捕捉信号起始脉冲和基于到达时间差(timedifferenceofarrival,TDOA)算法实现定位的原理,构建以局部放电位置点坐标为未知数的非线性规划问题,并利用禁忌搜索-粒子群优化(tabu search particle swarm optimization,TS-PSO)算法进行最优解求解。该算法可以避免非线性方程组求解时不收敛、解不唯一以及最小二乘法对初值要求高等问题,既保证了求解的速度,又能保证解的唯一性与准确性。实验室测试和现场测试验证了定位结果的有效性。展开更多
The understanding of the excitation mechanism of ultra high frequency (UHF) electromagnetic waves (EW) is essential for ap- plying UHF method to partial discharge (PD) detection. Since the EW induced by PD in gas insu...The understanding of the excitation mechanism of ultra high frequency (UHF) electromagnetic waves (EW) is essential for ap- plying UHF method to partial discharge (PD) detection. Since the EW induced by PD in gas insulated switchgear (GIS) contains not only transverse electromagnetic (TEM) wave, but also high-order transverse electric (TE) and high-order transverse magnetic (TM) waves, we analyzed the proportions between the TEM wave and the high order waves, as well as the influence of the PD position on this proportion, using the finite different time domain (FDTD) method. According to the unique characteristics of the waves, they are separated only ap- proximately. It is found that the high-order mode is the main component, more than 70%, of the electric field around the enclosure of GIS, and that with the increasing distance between PD source and inner conductors, the low frequency ( below about 800 MHz) component of EW decreases, but the high frequency component (above 1 GHz) increases, meanwhile the proportion of high-order components in EW could reach 77% from 70%. It concluded that the closer the PD source to the enclosure is, the easier high order EW may be excited.展开更多
基金Project supported by National High-tech Research and Development Program of China (863 Program) (2011AA05A121)
文摘The understanding of the excitation mechanism of ultra high frequency (UHF) electromagnetic waves (EW) is essential for ap- plying UHF method to partial discharge (PD) detection. Since the EW induced by PD in gas insulated switchgear (GIS) contains not only transverse electromagnetic (TEM) wave, but also high-order transverse electric (TE) and high-order transverse magnetic (TM) waves, we analyzed the proportions between the TEM wave and the high order waves, as well as the influence of the PD position on this proportion, using the finite different time domain (FDTD) method. According to the unique characteristics of the waves, they are separated only ap- proximately. It is found that the high-order mode is the main component, more than 70%, of the electric field around the enclosure of GIS, and that with the increasing distance between PD source and inner conductors, the low frequency ( below about 800 MHz) component of EW decreases, but the high frequency component (above 1 GHz) increases, meanwhile the proportion of high-order components in EW could reach 77% from 70%. It concluded that the closer the PD source to the enclosure is, the easier high order EW may be excited.
