Study on Faraday magneto-optical effect optical current transducer based on double closed-loop self-tuning system

With the development of State Strong Smart Grid, optical current transducer based on Faraday magneto-optical effect will become an ideal transducer to service the grid. However, due to the impact of temperature drift in practice, it can not work in the long-term stable situation. To solve the problem, the double closed-loop self-tuning method is proposed in this paper for the first time. This system includes two independent systems, the inner and outer loop system. It has theoretically demonstrated the mechanism how temperature drift affects the optical current transducer. And the mechanism has also been verified by a large number of experiments. At the same time, DSP system is used to analyze and process signals real timely. So the influence, caused by temperature drift, is offset, which will further enhance the measurement accuracy and operational stability of optical current transducer.