Exact and approximate expressions for mutual inductance coefficients and electrodynamic forces of co-axial turns and planar (disk) coils with current

Abstract

Object and purpose of research. The paper is concerned with the mutual inductance coefficients of co-axial circuits in a planar coil system. Known modifications for mutual inductance and electrodynamic forces in a system of co-axial circuits are written, and relations for their calculation are compared. Subject matter and methods. For this purpose the methods of mathematical physics and theoretic electric engineering are used. Main results. Alternative expressions are given for mutual inductance coefficients of co-axial coils and electrodynamic forces between the live coils. Curves of mutual inductance are plotted for planar coils with the distance between planes equal to 2 cm and the distance between coil turns Р equal to 1 сm and the distance between coil turns N equal to 0.5 сm, 0.4 сm & 0.3 сm. Conclusion. Relations have been derived for calculation of mutual inductance coefficients and electrodynamic forces at current passage in planar co-axial coils, which are very important for wireless transfer of power.

Keywords

• co-axial coils
• mutual inductance coefficients
• electrodynamic forces