Magnetic field of current transformer


  • Volodymyr Shevchenko Odessa National University, Ukraine
  • Olga Babiychuk Odessa National University, Ukraine



current transformer, a magnetic field, vector diagram, equivalent circuit, leakage flux, main magnetic flux, free part of the magnetic circuit, criterion of non-uniformity of magnetic flux distribution, current and angular errors of the transformer


Purpose. Development of equivalent circuits based on a detailed analysis of the magnetic field distribution in asymmetric CT structures and drawing up a mathematical model for calculating errors in relation to a multi-range built-in CT with a toroidal MC and a single-turn primary winding with different filling of the MC with turns of the secondary winding.

Methodology. Experimental study of the magnetic field distribution in a toroidal current transformer and transformer errors

Findings. The equivalent circuits of the current transformer, which adequately reflect the distribution of the magnetic field in the magnetic circuit of the transformer and a mathematical model for calculating the errors, were developed.

Originality. Based on the results of modeling in FEMM and experimental studies, the nature of the distribution of the magnetic field with partial filling of the magnetic circuit with turns of the secondary winding was determined, and equivalent circuits of the current transformer were developed.

Practical value. A mathematical model was developed for calculating the distribution of the magnetic field in the magnetic circuit and the transformer errors, on the basis of which a program for calculating the errors of current transformers was compiled.

Author Biographies

Volodymyr Shevchenko, Odessa National University

Ph.D, Associate Professor, Associate Professor of Electrical Machines Department, Odessa National University, Odessa

Olga Babiychuk , Odessa National University

Researcher, Researcher, Institute of Computer Systems, Odessa National University, Odessa


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How to Cite

Shevchenko, V., & Babiychuk , O. (2022). Magnetic field of current transformer. Electrical Engineering and Power Engineering, (4), 8–17.