摘要
针对特高压直流输电工程对控制与保护系统安全性的需求,基于相位敏感光时域反射仪(Φ-OTDR)对光纤链路微弱故障进行检测与定位。模拟了特高压直流输电工程控制保护系统的故障状态及环境信息,获得了Φ-OTDR系统底层时域背向散射的相位调制信息。对比分析了系统微弱故障分段、乘积分段信息熵定位算法对相同多类混杂信号的处理效果,结果表明,乘积分段信息熵算法在分段数为2时就能大大提升系统的信噪比,在采样周期数为100、40时系统对微弱故障的定位精度分别为±1.5 m、±2.0 m。
Objective With the continuous development of power transmission systems from west to east,the advantages of ultrahigh voltage(UHV)direct current(DC)transmission have become increasingly evident.The optical fiber link used in the UHV DC control and protection system may fail,exposing the system to risks.Existing methods for inspecting the performance of the optical fiber link in such systems are deficient.Only apart of the optical fiber can be used to test the attenuation using a light source and an optical power meter,and the quality of the optical fiber link requires manual evaluation.Faults along the optical fiber link and decreasing transmission performance are difficult to determine during operation and maintenance,thus representing a security risk to the UHV DC control and protection system.Because the use of a light source and an optical power meter to detect link faults in the control and protection system requires cooperation on the two ends of the link,it is difficult to determine the fault location,which is not conducive to failure cause analysis and rectification.Considering the high security requirements of UHV DC transmission,phase-sensitive optical time-domain reflectometry(Φ-OTDR)is employed to detect and locate weak faults in the optical fiber link of the control and protection system.Methods The proposedΦ-OTDR system prepared under laboratory settings comprised an optical transmission module,optical fiber interferometer,sensing optical fiber,optical receiver module,simulated weak fault source,signal processing module,etc.The fault status and environmental information of the key components of the UHV DC control and protection system are simulated,and information from time-domain backscatter phase modulation at the bottom of theΦ-OTDR system is obtained and analyzed experimentally.The information entropy algorithms of segmentation,multiplication,and integration are introduced to determine the failure status of the key components of the control and protection system of the simulated UHV DC transm
作者
阮峻
孙豪
朱志俊
田霖
徐宛丽
吴宝锋
孙小菡
Ruan Jun;Sun Hao;Zhu Zhijun;Tian Lin;Xu Wanli;Wu Baofeng;Sun Xiaohan(Kunming Bureau of EHV Power Transmission Company,China Southern Power Grid Co.,Ltd.,Kunming,Yunnan 650300,China;National Research Center for Optical Sensing/Communications Integrated Networking,Southeast University,Nanjing,Jiangsu 210096,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2021年第20期99-105,共7页
Chinese Journal of Lasers
基金
国家自然科学基金(61271206)
南方电网2019年科技服务项目(2019-41)。
关键词
光纤光学
直流控保
相位敏感光时域反射仪
故障定位
信息熵
fiber optics
direct-current control and protection
phase sensitive optical time domain reflectometer
fault location
information entropy
