The Research On Light Transmissivity Current Sensing Characteristic Based On Magnetic Fluids

The accurate measurement of current decides the safe, reliable and economic operation of power network. In the process of the development of power system, in order to reduce the loss of the economic line and improve the ability of economic power, the voltage level need enhance unceasingly, and so as the transmit energy. While the traditional current sensor can not meet the requirement of the development of electric power system as its large volume, difficult installation, poor ability to resist the electromagnetic interference.Replacing the traditional current sensor with optical fiber current sensor has become the trend of the development of large current power system. As the core of the sensing components, the optical properties and its magnetization characteristics of MHD makes MHD much valued in the current sensing research. So the current sensor based on magnetic modeling analysis has important theoretical and practical significance.In this paper, the main research work includes:After reading lots of literature about optical current sensor at home and abroad, the physical properties of the magnetic liquid and its special optical properties are analysed comprehensively and in depth.Then on the basis of combine of light transmissivity of the magnetic with the transmission properties of optical fiber, there is the design of a magnetic sensor.Under the influence of external magnetic field, the using of the application of Monte-Carlo method based on magnetic liquid simulates and analysizes the optical transmission characteristics of magnetic liquid.And establish a mathematic model of the magnetic current sensing system, then Genetic optimization algorithm was applied to magnetic current sensing system mathematical model for parameter optimization.On the basis of theoretical analysis, experimental sensor system is set up and the materials of the experiment are choosed. After analysis of experimental data and theory data, there is the conclusion that the magnetic current sensor can better response between electric current and magnetic liquid light transmittance.