Calculation and Theoretical Analysis on Mini Optical Current Transformer

In the article, relationship between sensing length and sensing performance has been studied. In order to realize microminiaturization of optical current transformer, sensing structure must be simplified first. Considering measure performance and material character, straight light path type optical current transformer which is made of block glass is the simplest structure. The Faraday optical rotation curve which reflects the relationship between Faraday angle and magneto-optical material length has been obtained. This paper has put forward a simple algorithm of knee point, which could fix the knee point on curve fleetly. The magneto-optical material length on knee point has a highest utilization ratio. According to the research, knee point position is related with glasses location and sectional shape of conductor. So the best location is the place nearest to conductor.