An Analytical Model for Predicting the Self-Capacitance of Multi-Layer Circular-Section Induction Coils

Induction coils are an important device for magnetic field measurement, and they are widely applied in the electromagnetic non-destructive testing and magnetotelluric measurement because of the simple structure and reliable performance, such as Barkhausen noise and eddy current testing. However, the self-capacitance of induction coils largely determines their performance especially at high frequencies, such as sensitivity to the variation of the magnetic field and the operation frequency range. To accurately predict the self-capacitance of multi-layer circular-section induction coils with hexagonal winding, an analytical model is proposed in this paper. The comparative study between the existing models and the new hexagonal model indicates that the hexagonal model has the higher prediction accuracy for the induction coils with standard or flyback winding. Moreover, the dependencies of the self-capacitance on the geometrical and winding parameters are investigated for the purpose of optimizing the self-capacitance of multi-layer circular-section induction coils.