光纤传感器在高压设备在线测温系统中的应用

电气设备在高电压、大电流的状态下运行时,其工作可靠性与热密切相关即发热温升是关键问题之一。为实时监测开关柜及接头在运行时的温度状态,针对其高压、强磁场工作环境提出了基于分布式光纤传感器的开关柜接点温度在线监测系统设计方案,方案采用了空分和波分复用的光路系统,并运用一种新的解调方法即利用瑞利散射信号来解调反斯托克斯信号,大大提高了信噪比。此外,该系统中光纤同时被用作传感器和信号通道以使终端机远离测量现场,从而彻底避免了强电磁场的干扰。由于光纤本身不带电,抗射频和电磁干扰,防燃、抗腐蚀、耐高压、耐辐射,能在各种恶劣环境中工作,对提高高压开关柜等高压电气设备运行的可靠性乃至电力系统运行的可靠性具有相当的实用价值。

HV Switchgear Temperature On-line Monitoring System with Distributed Optical Fiber Sensor

A new technology,the distributed optical fiber Raman photonic sensor system(DOFRPS),which is used for the real-time measurement of temperature field in the space,is widely used in electric power system.In this paper,the working principle and structure of HV switchgear temperature on-line monitoring system based on distributed optical fiber sensor was introduced,and it was compared with traditional thermo detector.Secondly,spontaneous Raman scattering photons were the carriers of temperature signal.A resolution to measure temperature of HV(high voltage) switchgear was brought forward,which was used in the circumstance of HV and powerful electromagnetic field.The configuration and demodulation method of the DOFRPS system were introduced along with the selection of LD wave length and signal noise ratio.In respect to the design,the new optical circuit of space division multiplex and wavelength vision multiplex was used,and the signal processing system of the sensor was also established,as well as the HMI software to predict and warn for fire hazard was set up.During long-term test,the system was normal,and the temperature curve was not broken,but smooth,which means that the system is powerful to resist electromagnetic interference.The project is practicable and should be widely used in the state monitoring of HV electrical facilities in electrical power plants and substations.