Performing Analysis of Current Transformer in Short Circuit and Open Circuit Conditions By ANSYS@Maxwell

Year 2021, , 189 - 194, 31.03.2021

Yıldırım Özüpak

https://doi.org/10.18185/erzifbed.763314

Abstract

Calculation of the design parameters of the current transformers (CT) is very complex due to the magnetic and thermal properties, the complexity of the structures, the different ferromagnetic properties of the materials and the non-linearity of the B-H curve of the core material. Secondary output of these transformers is used for both measurement and protection circuits. Therefore, the accuracy of the current transformers is important. In this study, a current transformer is modeled as 2D using the Finite Element Method (FEM). ANSYS@Maxwell program was used for magnetic and thermal analyzes of current transformers based on finite element method. The transformer analyzes were performed in 2D under open and short circuit conditions. The results obtained from the analyzes revealed that the dispersed electromagnetic flux distribution occurred in the CT core, which caused an error in the secondary current of the CT and the unintended working conditions occurred in the protection circuits.

Keywords

Electromagnetic field, Thermal analysis, Current transformer, Finite Element Method (FEM)

Performing Analysis of Current Transformer in Short Circuit and Open Circuit Conditions Using ANSYS@Maxwell

Abstract

Calculation of the design parameters of current transformers (CTs) is very complex due to their magnetic and thermal properties, complexity of their structure, different ferromagnetic properties of the materials and the nonlinearity of the B-H curve of the core material. The secondary output of these transformers is used for both measurement and protection circuits. Therefore, AT's accuracy must be very good and precise. In this study, the transformer is modeled as 2D using the Finite Element Method (FEM). ANSYS@Maxwell program, which realizes a solution based on finite element method, has been used in magnetic and thermal analysis of the current transformer. Analyzes of the transformer were carried out in 2D under open and short circuit conditions. From the results obtained from the analysis, the scattered electromagnetic flux distribution occurred in the core of the current transformer, which caused the secondary current of the CT to be erroneous. Therefore, it has been observed that unwanted operating conditions occur in the protection circuits..

Keywords

electromagnetic field, thermal analysis, current transformer, finite element method(FEM)

References

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