深圳大学学报理工版

通过对电缆中间接头局部放电现象的监测可以及时判断其中间接头的绝缘状况,并及早发现绝缘缺陷,降低配电网电缆故障率.提出一种基于相敏光时域反射仪(phase-sensitive optical time-domain reflectometry, φ-OTDR)的分布式光纤传感系统,以相邻弱光栅间的光纤作为传感单元,通过检测相邻弱光纤光栅的干涉信号,可以得到电缆中间接头局部放电声波振动信号的频率、相位和位置等相关信息,从而判断局部放电的强弱及放电位置.实验模拟电缆中间接头局部放电情形,搭建电缆接头局部放电光纤监测系统.在10 kV电压等级下进行实时监测实验,成功检测出局部放电产生的声波信号,其频谱主要分布于9～15 kHz.将传感光纤与电缆复合,或沿电缆铺设,能够做到实时的分布式在线监测.

Monitoring the partial discharge of the intermediate joint of cable can help to judge the insulation condition in time and find latent defects in cable joints as early as possible, so as to reduce occurrence of insulation fault. In this paper, we propose a distributed acoustic sensing(DAS)system based on the enhanced phase-sensitive optical time-domain reflectometry(φ-OTDR)technology. By detecting and analyzing the interference signals between the two adjacent weak fiber Bragg gratings(FBGs)in optical array which is paved along with cable, we can obtain the frequencies, phases, and positions of acoustic signals generated by partial discharge of the cable joint, and then determine the strength and location of partial discharge. In our experiment, by simulating partial discharge of cable intermediate connector in laboratory environment at the voltage of 10 kV, the fiber optic monitoring system is set up,and the acoustic signal by partial discharge is successfully detected. Experimental results show that the proposed DAS system can accurately distinguish weak signal with different frequency and have better frequency response from 9 kHz to 15 kHz. The DAS system can achieve the real-time distributed on-line monitoring of partial discharge by the combination of sensing fiber and cable.

引言
1 局部放电监测原理分析
2 系统搭建
3 实验结果及分析
4 结语

图1 解调系统原理图<br/>Fig.1 Diagram of the interrogation system

图1 解调系统原理图
Fig.1 Diagram of the interrogation system

图2 局部放电模拟发生装置<br/>Fig.2 (Color online)Partial discharge analog generator

图2 局部放电模拟发生装置
Fig.2 (Color online)Partial discharge analog generator

图3 局部放电监测结果<br/>Fig.3 Detection results of the partial discharge

图3 局部放电监测结果
Fig.3 Detection results of the partial discharge

图4 10 kV电压下监测到的局部放电信号<br/>Fig.4 The result of partial discharge at 10 kV voltage

图4 10 kV电压下监测到的局部放电信号
Fig.4 The result of partial discharge at 10 kV voltage

图5 解调信号频谱图<br/>Fig.5 The frequency spectrogram of the demodulated signal

图5 解调信号频谱图
Fig.5 The frequency spectrogram of the demodulated signal

图6 手持式TEV检测结果图<br/>Fig.6 The result of handheld TEV

图6 手持式TEV检测结果图
Fig.6 The result of handheld TEV

[1] 张义龙, 李立学, 郑益慧,等.110 kV电缆中间接头局部放电高频电磁检测与优化[J].电气自动化,2015,37(6):102-105.
[2] GROSS D W, SOELLER M. On-site transformer partial discharge diagnosis[C]// IEEE International Symposium on Electrical Insulation. San Juan, USA: IEEE, 2012: 558-564.
[3] WANG Youchen, ZHU Chaojie, WANG Qiaohua, et al. Processing of partial discharge ultra-high frequency signals from a true size transformer[C]// IEEE International Conference on Solid Dielectrics. Bologna, Italy: IEEE, 2013: 1012.
[4] MA Guoming, LI Chengrong, MU Ruiduo, et al. Fiber Bragg grating sensor for hydrogen detection in power transformers[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2014, 21(1): 380-385.
[5] POSADA-ROMAN J, GARCIA-SOUTO J A, RUBIO-SERRANO J. Fiber optic sensor for acoustic detection of partial discharges in oil-paper insulated electrical systems[J]. Sensors, 2012, 12(4): 4793- 4802.
[6] 孙廷玺,陈浩,钱森,等.光纤传感技术在局部放电监测的研究进展[J].高压电器,2018, 54(11):9-16.
[7] ROHWETTER P, EISERMANN R, KREBBER K. Distributed acoustic sensing: towards partial discharge monitoring[C]// The 24th International Conference on Optical Fibre Sensors. Curitiba, Brazil: SPIE, 2015, 9634:96341C.
[8] ZHANG Tongzhi, PANG Fufei, LIU Huanhuan, et al. A fiber-optic sensor for acoustic emission detection in a high voltage cable system[J]. Sensors, 2016, 16(12): 2026.
[9] 李晓敏, 高妍, 王宇. 基于光纤传感技术的局部放电超声信号检测方法研究[J]. 传感技术学报, 2017,30(11): 5-10.
[10] 黎威,张永佳.基于弱光栅阵列的增强相位敏感光时域反射仪振动传感系统[J].中国激光,2018,45(8):234-241.
[11] TANG Jianguan,LI Liang,GUO Huiyong, et al. Distributed acoustic sensing system based on continuous wide-band ultra-weak fiber Bragg grating array[C]// The 25th International Conference on Optical Fiber Sensors. Jeju, South Korea. IEEE, 2017: 1032304.
[12] 刘胜, 韩新颖, 熊玉川,等. 基于弱光纤光栅阵列的分布式振动探测系统[J]. 中国激光, 2017, 44(2): 313-318.
[13] 张晓峻, 康崇, 孙晶华. 3×3光纤耦合器解调方法[J]. 发光学报, 2013, 34(5): 665- 671.
[14] TODD M D, SEAVER M, BUCHOLTZ F. Improved, operationally-passive interferometric demodulation method using 3×3 coupler[J]. Electronics Letters, 2002, 38(15): 784-786.

备注

引言

1 局部放电监测原理分析

2 系统搭建

3 实验结果及分析

4 结语

期刊信息

备注

引言

1 局部放电监测原理分析

2 系统搭建

3 实验结果及分析

4 结 语

期刊信息

4 结语