Study of number and size of air-gaps in core of shunt reactors in tranmission lines of high and supper high voltages



  • Pham Minh Tu School of Electrical Engineering, Hanoi University of Science and Technology
  • Dang Quoc Vuong School of Electrical Engineering, Hanoi University of Science and Technology
  • Bui Duc Hung (Corresponding Author) School of Electrical Engineering, Hanoi University of Science and Technology



Cuộn kháng bù ngang, Phương pháp giải tích, Phương pháp phần tử hữu hạn, Số lượng khe hở, Kích thước khe hở, Điện cảm


The air-gaps are designed on the core of shunt reactors to increase the reluctance of the magnetic circuit, to increase the stored energy and to obtain the required reactive power. The volume of the air-gaps depends on the capacity of the shunt reactors. In fact, the more reactive power the shunt reactor has, the more volume and length of the air-gap the shunt reactor needs. However, the leakage flux appearing around the air-gap will directly affect to the inductance parameters and the reactive power of the shunt reactor. For a large air-gap, the leakage flux appearing around the air-gap will have a large radius and will loop into the winding, resulting in a large total inductance. Therefore, dividing a large length air-gap into smaller air-gaps distributed on the core will reduce the total inductance value. The number of the air-gaps to be splitted depends on the capacity of the shunt reactor and the mains voltage. In this paper, the authors combine the analytical method based on the theory of magnetic circuit model to determine the main parameters of the shunt reactor, then the finite element method is used to determine the number of the air-gaps and the appropriate air-gaps size on the core of the shunt reactors.


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How to Cite

Phạm Minh Tú, vuong dang quoc, and Bùi Đức Hùng. “Study of Number and Size of Air-Gaps in Core of Shunt Reactors in Tranmission Lines of High and Supper High Voltages”. Journal of Military Science and Technology, no. 80, June 2022, pp. 23-30, doi:10.54939/1859-1043.j.mst.80.2022.23-30.



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