Using a fiber optic sensor for registration of pulsed plasma discharge current

Abstract

The problem of increasing the accuracy of recording the pulse shape of a rapidly changing current of a powerful plasma emitter under conditions of powerful electromagnetic interference is considered. To register high-current pulsed discharges, it is proposed to use a polarimetric fiber-optic current sensor based on a Spun-type fiber. Using the indicated current sensor, a technique for recording high-current pulsed discharges of a plasma emitter in the mode of time profiling of the current pulse of two high-voltage capacitive storage devices with a total energy of up to 1800 kJ is realized. The discharge chamber, power supply circuits, and the formation of a plasma discharge are described. The design and principle of operation of a prototype of a two-pass polarimetric fi beroptic sensor with a Spun-type fiber and a Faraday compensator of mutual optical anisotropy are presented. The general scheme of current measurements, the sensor calibration scheme is presented, and the experience of using a prototype sensor for measuring high-power pulse currents is described. The features of the preliminary calibration of the sensor are discussed. The results of measuring the current by optical and traditional recording methods based on the Rogowski coil and Hall sensors are compared with each other, and a noticeable increase in the accuracy of reproducing the current pulse shape by the optical recording method is noted. Possible options for upgrading a fiber-optic sensor to expand the range of current recording are considered.