Analysis of the Behavior of an Optical Current Transformer Using an Equivalent Circuit

In pursuit of applying new technologies in power systems, new generations of instrument transformers based on optical principles have been built that help to decrease the problems associated with the presence of a ferromagnetic core in the Conventional Current Transformers (CCT). To study the behavior of these optical devices some authors have proposed different circuit models that represent an equivalent circuit for the apparatus. Taking as starting point some of those previous works, in this paper an equivalent circuit model to represent an Optical Current Transformer (OCT) is proposed. This circuit is composed of a low pass and a band pass filters, when it is simulated and analyzed yield similar performance than those obtained by other author´s approaches. Furthermore, comparing the results with studies made about CCT in the presence of transients phenomenons the performance of the OCT was better than the CCT.