Development of a Fiber-Optic Current Sensor With Range-Changing Facility Using Shunt Configuration

Considering that a magneto-optic Faraday effect may play an important role in the design of multirange electric current measurements, a novel range-changing facility using shunts is proposed and fabricated to demonstrate the effectiveness of an intensity-modulated fiber-optic current sensor. The current sensing over three orders of magnitude is demonstrated in a single-mode fiber of 633-nm wavelength with a suitable laser source. The design of the sensor is based on a dual prototype of the Rogowsky coil carrying the laser beam encircling the current path. The experimental results are presented which agree well with the theoretical predictions of the performance analysis of the sensor.