Equivalent circuit of high frequency inductor to consider eddy currents and resonance

Issue title: 20th International Symposium on Applied Electromagnetics and Mechanics

Guest editors: Theodoros Theodoulidis, Christos Antonopoulos, Nikolaos Kantartzis, Ioannis Rekanos and Theodoros Zygiridis

Article type: Research Article

Authors: Liu, Qiao^a; | Otomo, Yoshitsugu^b | Gong, Yunyi^a | Igarashi, Hajime^a

Affiliations: [a] Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan | [b] Graduate School of Engineering, Nagasaki University, Nagasaki, Japan

Correspondence: [*] Corresponding author: Qiao Liu, Graduate School of Information Science and Technology, Hokkaido University, 060-0814, Sapporo, Japan. Tel.: 81 802 797 8643; E-mail: [email protected]

Abstract: The resistance and inductance of an inductor working at high frequencies depend on frequency because of eddy currents caused by the skin and proximity effects. In addition, the stray capacitance among winding coils would give significant influence. This paper proposes an equivalent circuit model which can consider the displacement and eddy currents simultaneously in frequency and time domain. In the proposed circuit model, the capacitance and complex inductance are determined by solving electrostatic and magnetostatic equations with finite element method (FEM). It is shown that the input impedance of an air-core coil is consistent with that computed by FEM at low frequencies. Moreover, the former is shown to be consistent with the measured result.

Keywords: Inductor, equivalent circuit, eddy current, displacement current, self-resonant

DOI: 10.3233/JAE-220160

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S275-S282, 2023