All Fiber Optic Reflective Sensor Design And Application Of Measure The Current In The Smart Grid

On the basis of optical fiber current sensor on the online monitoring application of smartgrid, this thesis describes the non-contact quick analysis based on magneto-optic modulationfunction of polarized light small deflection angle measurement technology which is widelyapplied to teaching and research, industrial and mining enterprises, and health and so forthother fields of nondestructive measurement, for instance optical medium Verdet constant,sugar concentration and the magnetic field research of macro space, confining analysis andobserve the internal magnetic field of the atomic structure etc including many other relatedphysical quantities measurement. With the resistance to electromagnetic interference and largedynamic range, small size, easy to digital data processing, this essay introduces a newmagneto optical medium such as liquid crystal.Focusing on analyze the basic theory of fastFourier transform applies in the application of measuring deflection angle of medium of thefull optical fiber reflection current sensor.First, the structure design of optical fiber current sensor head by the classificationcomparison, this dissertion shows the research and its practical significance at home andabroad, and gives the structure of the paper and the research content.Second, the basic principle of polarization light is introduced, and to carry on thetheoretical derivation in the optical signal transmission using two kinds of methods ofmathematical analysis and Jones matrix.Third, introduces the basic theory of Faraday magneto-optic effect and its development,alternating current simulation is carried out in view of malus law, the modulation accuracy is briefly analyzed.Forth, this essay proposes a new magnetic medium of liquid crystal which introduceslight polarization principle and simulates its measuring system. considers the method of fastFourier transform to detect the harmonic and established the harmonic division ways of thesignal test,accordance with the relationship between the light deflection angle and amplituderatios,utilizing the fast Fourier transform to receive different frequency signal amplitude ratiosfor the measurement method of optical dielectric polarization rotation angle to analysis theoutput signal of optical medium. Experimental design on account of TMF320F2812opticalfiber sensor is proposed, simulation test and verify the response of spectrum analysis in ACsine wave excitation.Finally, Faraday mirror are introduced in the optical fiber current sensor to inhibit theeffects of the linear birefringence, theoretically analyzes the orthogonal conjugate mirror andexperiment realization. Analyzes theory and formula derivation of the modulation error effectand carrys out numerical calculation and simulation.