Influence of the Aging of Sensitive Optical Fiber on the Measurement Accuracy of All-Fiber Optical Current Transformer System
The influence of aging of sensitive optical fiber devices on the measurement accuracy of the AFOCT system is studied.First-ly,based on Faraday magneto-optical effect,the transmission model of the AFOCT system is established with the help of Jones matrices.With Jones matrices of the sensing fiber having birefringence,the measured value of injected current to the system is given.Further,a measurement system is built to experimentally characterize the birefringence of the sensing fiber.Also,the Jones matrix of the sensing fi-ber and the transmission model of the AFOCT system are calibrated to minimize the measurement error of the injected current to the AFOCT system.Finally,the accelerated aging experiment is carried out for the sensing fiber,which corresponds to the actual operation of this fiber for 3 months.Afterwards,the birefringence of the sensing fiber after aging is measured.Then,by applying the calibrated transmission model of the AFOCT system,the erroneous value of the system injection current is obtained.The experimental results show that the obtained system injection current has a relative error of 0.2955%after the 3 months aging of the sensing fiber,which is not ac-ceptable for the actual operation.
all-fiber optical current transformerjones matrixbirefringenceaging of sensitive optical fibercalibration