摘要
局部放电(PD)是变电站电力设备绝缘劣化的主要表征之一。对局部放电的监测与定位是设备绝缘故障预警的重要手段。目前变电站设备局部放电定位主要是基于特高频(UHF)电磁波到达时间差法开展的。此方法需要极高采样率和时间同步精度,装置成本较高。因此,该文提出基于接收信号强度功率(RSSI)和最大似然(ML)估计的特高频局部放电测向(DOA)方法。首先,离线测试得到各特高频无线传感器的接收信号模型;然后,利用传感器阵列接收到的幅值和最大似然估计方法得到初步测向结果;最后,利用插值拟合、聚类分析等方法提高测向精度以得到最终的局部放电源方位角。实验测试结果表明,该方法的平均测向误差小于7°,且成本更低、现场使用更加便捷。
Partial discharge is one of the main reasons of electrical equipment insulation deterioration in substations.The detection and localization of partial discharge(PD)using ultra-high frequency(UHF)antennas is an important means for equipment fault warning in substations.UHF PD localization system is usually based on time-difference of electromagnetic wave signal.However,this system requires high sampling rate and time synchronization accuracy,which has high cost.This paper studied the feasibility and accuracy of PD direction of arrival(DoA)using power of UHF received signal strength indicator(RSSI)and maximum likelihood(ML)estimation.First,the UHF antenna power pattern was achieved in the offline experiment.Then,a method using maximum likelihood estimator was proposed to handle PD direction of arrival estimation and obtain the preliminary orientation results.Last,in order to obtain the final results,interpolation and clustering were employed to improve the resolution.In a laboratory test,the experimental results show that the average error of direction of arrival is less than 7°,and the cost is lower and the use is more convenient.
作者
吴凡
罗林根
王辉
盛戈皞
江秀臣
Wu Fan;Luo Lingen;Wang Hui;Sheng Gehao;Jiang Xiuchen(Department of Electrical Engineering Shanghai Jiao Tong University,Shanghai 200240 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2020年第12期2689-2697,共9页
Transactions of China Electrotechnical Society
关键词
变电站
局部放电
接收信号强度
最大似然估计
到达角度
Substation
partial discharge
received signal strength indicator
maximum likelihood estimator
direction of arrival
