Design And Implementation Of Optical Fiber Temperature Measurement System Based On Power Cable

Power cable is the core equipment of power transmission in power system,and its operation status is the guarantee of stable operation of power grid.Cable faults are mostly caused by the decrease of insulation performance caused by temperature rise.Therefore,monitoring the operating temperature of cables has become an important means to prevent power accidents.With the continuous development of optical sensing technology and the characteristics of optical fibers such as insulation and non-interference from electromagnetic field,optical fiber temperature measurement technology has been widely used.This paper is based on the design of optical fiber temperature measurement system for power cables.The specific research contents are as follows:Based on the theory of optical time domain reflection and Raman scattering,the temperature signal demodulation algorithm of Raman scattering is deduced through theoretical calculation and analysis,which provides theoretical basis for the design and development of optical fiber temperature measurement system.The main monitoring indexes and accuracy of optical fiber temperature measurement system(temperature measurement ±1?)and distance measurement(2000±2m)are proposed.The structure design of optical fiber temperature measurement system is carried out,including hardware design and software development.According to the theoretical calculation and monitoring index,the related technical parameters of optical and electrical signals are analyzed,the types of optical and electrical signal equipment are selected,and the accurate distance measurement ranging(2000±2m)is realized.On this basis,the hardware platform of optical fiber temperature measurement system is constructed.At the same time,the software system matching the hardware platform is developed: the Qsys bottom design based on NIOSII soft core processor is completed by Verilog language,the temperature signal demodulation program based on optical fiber is developed by Eclipse software,and the real-time monitoring with the host computer is realized by ethernet.Through field test and data fitting research,the attenuation coefficient difference was calibrated,and the temperature demodulation formula of the optical fiber composite cable was obtained,which ensured the temperature measurement accuracy of ±1?.Then the optical fiber temperature measurement system based on the power cable was developed.At the same time,it provides a technical solution for solving similar engineering problems.