The Research Of Current Sensing Based On Rogowski Ang FBG

The power industry is the basic industry of national economic construction andcurrent measurement plays an extremely important role in power industry to providinginformation needed for measurement, control and protection in the power system. With thedevelopment of power system, especially for EHV, UHV voltage level of development, thevoltage level is getting higher and higher and transmission capacity is growing more andmore high, the conventional current transformer can’t meet the modern technicalrequirements, because its large volume, difficult installation, weak electromagneticinterference resistant ability and the poor electrical insulation.Fiber Bragg grating currentsensor because of its electrical insulation, small volume, high sensitivity, has becomehotspot in the field of current sensor research, having wide development and applicationprospect of power generation, power transmission, electric power system field.This article proposed one kind current sensor based on Rogowski coil drawing fromthe existing fiber Bragg grating current sensor technology research, the main workincludes:The equivalent model of Rogowski coil based on the theory of photoelectric hybridcurrent sensor is analyzed in detail, and the physical characteristics of magnetostrictivematerial is studied.And the sensing characteristics of fiber Bragg grating sensor is studiedin depth. A new structure based on Rogowski coil current sensor is designed through theanalysis of the relation between the measurement and sensing, combining the applicationsof Rogowski coil and magnetostrictive materials in current fiber Bragg grating sensing.The final demodulation scheme of fiber Bragg grating current sensing system based onRogowski coil is determined after the research of the commonly used optical fiber gratingdemodulation method on the current stage and the analysis of the advantages anddisadvantages of various demodulation methods, combining the characteristics of fiberBragg grating current sensor designed, that is tunable F-P filter demodulation system. Andthe selection of the core device and the design of light path and circuit are completed inthe demodulation system. According to the fiber Bragg grating current sensing system based on Rogowski coil designed, a fiber Bragg grating current sensor experimentalsystem is constructed to test the performance of the sensor, and the experimental resultsare further analyzed and researched.