Measurement of AC current using an optical fibre sensor

Abstract

In the power industry, current is measured for metering and protection purposes. For said measurement, we demonstrated an optical fibre sensor using a single Fibre Bragg Grating (FBG) for measuring AC current for this paper. The sensor head is based on an FBG encased in a polymer-half-field metal cylinder, embedded in a magnetic material at the measuring point with the characteristics of an all-optical high pressure sensitivity. The operating mechanism is that the sensor can be attracted by the induced magnetic force created by the solenoid along one radial direction only, and responds to an axial force on the magnetic rod attached to the round plate, creating an axial attraction on the FBG.

Electric current sensors: a review

“…Magnetostrictive and force current sensors. In the fibre Bragg grating current sensor, described by Zhao et al (2006), Reilly et al (2006 and Cheng et al (2007), the optical fibre sensor measures the force on a magnetic element attracted by a solenoid, which is supplied by the measured current. The performance of these sensors is poor, and we consider their potential to be weak.…”