变压器局部放电超宽带射频定位技术的试验分析  

Experimental Analysis on Partial Discharge Location in Power Transformers Using UWB RF Method

作　　者：常文治[1] 唐志国[1] 李成榕[1] 王浩[1] 郑书生[1] 

机构地区：[1]华北电力大学高电压与电磁兼容北京市重点实验室,北京102206

出　　处：《高电压技术》2010年第8期1981-1988,共8页High Voltage Engineering

基　　金：国家自然科学基金(50477040)~~

摘　　要：超宽带射频定位技术结合局部放电射频信号超宽带检测与天线阵列技术并以最短光程原理为基础,是变压器局部放电定位的新方法。为探索该技术在实际中的应用,研制了频带2～8GHz的新型平面等角螺旋天线作为定位传感器,其放电射频信号的耦合输出波形平均上升时间约150ps,单个脉冲振荡时间约200ps,从而限定时延测量误差<200ps;提出了空间网格搜索定位算法,避免传统的解析算法容易由于时延测量值及波速参量的微小误差而导致定位结果发散或误差偏大的缺点。利用新型定位传感器及空间网格搜索定位算法在220kV真实变压器上开展局部放电超宽带射频定位研究并建立了一套能够有效应用的定位系统,对设定故障源的检测灵敏度≥100pC,波速约19.8cm/ns时定位精度最高,平均定位误差约30cm。Ultra-wideband （UWB） radio frequency （RF） partial discharge （PD） location technique is a new method for PD source location on power transformers, which is based on multi-antenna PD detection and Huygens-Fresnel principle. In this paper, a novel sensor with 2-8 GHz bandwidth for UWB RF detection was designed. By optimi zing the constitution and parameters of the antenna, the average measured rise time of the coupling output waveform can be up to 150 pico-seconds （ps） , while its single oscillation time duration reaches 200 ps or so, therefore the time difference of arrival （TDOA） resolution can be improved within the scope of 200 ps. A new location algorithm named the Space-Grid-Search algorithm was proposed which could greatly eliminate the divergent effect of analytical method. Two typical artificial PD models were applied to a real 220 kV transformer. Then experiments were carried out for PD location on the transformer using UWB RF technique. For preference PD sources, the location results in dicate that the average least error is 30 cm when the RF electromagnetic wave speed is set as 19.8 centimeters per nanosecond or 19.9 centimeters per nanosecond, sensitivity of the detection system is not less than 100 pC.

关 键 词：变压器 局部放电 超宽带 射频 定位 传感器 算法 

分 类 号：TM835[电气工程—高电压与绝缘技术]