Fiber-Optic Sensor for MA Current Measuring

A fiber-optic current sensor implementing the differential measurement to measure currents up to tens of megaamperes is proposed. The sensor is based on a reflective interferometer with a sensing coil made up of two spliced highly birefringent spun fibers with different sensitivities and wound in opposite directions around the current conductor. Mode coupling occurring at the splice has been shown to disturb the output signal, requiring modifications to the signal processing. The 50 MA range sensor has been experimentally demonstrated.