A high-accuracy optical current transducer for electric power systems

An optical current transducer (OCT) employing a new, simple technique to measure electric current has been developed. The technique is based on a fundamental analysis of the Faraday effect. The disturbing effects of temperature on the glass sensing element can be overcome. By aligning the transmission axis of the polarizer at specific angles, it is shown that the OCT´s output is independent of temperature. High-accuracy measurements are thereby possible over a wide range of temperatures. Two practical OCT designs for extra-high-voltage power systems are compared