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Design of 25 KA Current Injection Transformer Core with Finite Element Method
HOSSEIN HEYDARI, MOHSEN ARIANNEJAD, FARAMARZ FAGHIHI
Iran University of Science and Technology, Tehran, Iran
Abstract—.Since Current Injection Transformers (CIT) are within the major group of the standard type test equipments in electrical industry, their performances are very crucial. CIT is widely used for standard tests in electrical industry for a variety of purposes, such as relay protection systems consisting of insolated HV conductor, fuses, SF6 switches, low voltage switches (ACB, and MCCB), sectionalizing switches, and so on With the help of Finite Element Method (FEM), some of the prominent problems can be solved. This paper attempts to fill this void by making direct comparison of the localized flux in 25KA CIT with three-limb single phase transformer cores.
Flux distribution is solved by Ansys5.4 software .Then we compare results of the three-limb single phase transformer cores together and we obtain effect of overlap size of the core laminations on its hot-spot temperature.