A method for monitoring partial discharge of electrical cable based on magneto-optic crystal optical fiber current sensor

We develop an on-line monitoring method for partial discharge of high-voltage electrical cable. The optical fiber current sensor construction that combines the magneto-optic material with the ferromagnetic ring concentrator. We carry on the simulation and analysis to air gap magnetic field of the ferromagnetic ring concentrator using the COMSOL Multiphysics finite element analysis software, find the method to solve the air gap size of ferromagnetic ring concentrator and the placement of the magnetic field crystal according to the magnetic field distribution rule. We have studied distinctive features of the response of a fibre-optic current sensor with a magneto-optic crystal sensing to short current pulses. The response of the current sensor to the pin-to-plate discharge model of electrical cable at different voltage levels has a linear relationship and its duration is determined by the relationship between the current pulse duration.