Study On The Faraday Mirror-typed Optical Current Transformers

The profound influence of investigation and exploitation of the practical Optical Current Transformer (OCT) upon the industry of power delivery in our country will be brought in the future. It is just about the significance of choosing this subject.OCT is a kind of the Electrical Current Transformer (ECT). On account of its advanced technology, the requirement of OCT in electrical metrology industry is very urgent. However, to this day, the technology of OCT is still on the road to practical research and full of difficulties and challenges. The questions on the effects of linear birefringence and reflection-induced retardance upon the polarization state of the output light are ones of the kernel technology problems during the practical application of the bulk glass current transformer.A project of Faraday mirror-typed optical current transformer (FMOCT) with turn-back optical paths is proposed in this paper. All the optical processes are analyzed and simulated using matrix theory. The results show that FMOCT can solve above technology problems very well and double the sensitivity. By the way of computer simulation, the effects of linear birefringence or reflection-induced retardance or both of them upon the polarization state of the output light are investigated, the effects of the characteristic parameters of two important appliances of FMOCT, Faraday mirror (FM) and non-polarization beam spliter (NPBS), upon the polarization state of the output light are analyzed. Besides, the influences of temperature and stray magnetic field upon the characteristic parameters of FM and NPBS are also analyzed experimentally. At the same time, light coupling technology theory for FMOCT is also studied. Processing design of the optical paths of the FMOCT is given, too. Investigating the effects of...