Design And Simulation For Full Optical Fiber Current Sensor System Based On Optisystem

Because of hign signal transmission speed,strong ablity in resistance to electromagnetic interference, high voltage measurement capability, small size and so on many unique advantages.Full optical fiber current sensor was anticipated widely, which have great application prospect in electricity, fire, military, intelligence and other areas.After decades of continuous research and development,It has made many achievements, and some products have also been put into operation as well achieved some effect,which still have a long way to go.However, As a relatively new type of sensor, which still have long distance from the large-scale application.Such as the system stability,precision and linear birefringence exists that polarized light sensorin the medium, temperature, the experiment cost still higher issues to be solved, it alsoindicates that the full optical fiber current sensor has great developmental prospects and research value.Linear birefringence is the main error source in the system, which usually because of the phase difference produced in the optical fiber transmission between two orthogonal polarization modes of line polarized light,and become a circularly polarized light or elliptically polarized light,so that reduce the sensitivity of the system and even sensitivity to zero that cause error.In this paper, the third chapter reseach on the problem, discusses the forming reason, using the formula of linear birefringence phase difference is deduced. And the simulation using the matlab software to calculate, the Faraday effect about Angle with the rotating circularly polarized light, the relationship between phase difference is set up by the fifth chapter based on the circular birefringence of the simulation system laid a foundation.The fourth chapter of this paper focus on the key areas of light path and the signal processing part in the full optical fiber current whole system of.Optical path of the light source, optical fiber analyzer, the photoelectric detector are introduced, the signal processing mainly concentrated in the preamplifier circuit, low pass filter circuit, adc circuit aspects has carried on the design and analysis, use of protel software to draw the circuit diagram.The fifth chapter, on the basis of the principle of the nature of Faraday effect circular birefringence use Optisystem software has set up a simulation system for the whole.First simulation the selection of light sources and linear polarized wave plate will be converted to circularly polarized light optical path system, the intensity and wavelength light source of the initial value, verify the half wave plate converts linear polarized to a circularly polarized light, for subsequent overall simulation system provides a theoretical and data support.Then the full optical fiber current system to the whole building and simulation, using sine wave phase modulation and triangular wave phase modulation, the output light intensity signal and modulation signal, the simulation verification can effectively reduce the project cost, save time.Finally, the circuit noise exist in the system and the polarization error are studied.