A Photonic Transducer-Based Optical Current Sensor Using Back-Propagation Neural Network

We introduce and experimentally demonstrate a novel optical current sensor using a coil combined with an optical transducer for metering and protective relaying application. The transducer modulates the intensity of the lightwave corresponding to the coil output. A back-propagation neural network is designed for the nonlinearity compensation of the sensor at different temperature. In addition, the impact of the optical power drift has been eliminated by an optical-pumped biased dc voltage signal. The result shows that the sensor errors are within the range of 0.17% when increasing the current from 100 to 600 A. And a maximum error of 0.18% is recorded over -20 °C to 70 °C range.