Multifunction realization of active electronic current transformer

In order to fit for the urgent requirement of the digital substation, the research of electronic current transformer (ECT) attracts more and more attention. The multifunction of ECT is especially studied in order to expand its application range. In this paper, a type of active ECT is introduced firstly. The redundant backup design of high-voltage circuit is presented after that. It will be greatly helpful for the improvement of stability and reliability of active ECT. The multifunction of low-voltage side circuit is also discussed carefully. The local display, harmonic analysis and remote communication between ECT and master computer are all designed and realized. Therefore, the application field of active ECT will be expanded significantly. The validities of above circuits are all illustrated in Lab at last.