EXACT ANALYTICAL AND APPROXIMATE ASYMPTOTIC CALCULATION METHODS TO DETERMINE THREE-DIMENSIONAL ELECTROMAGNETIC FIELD NEAR CONDUCTING BODY WITH FLAT SURFACE

Abstract

The analytical solution of the three-dimensional quasi-stationary electromagnetic field problem for a current located near conducting body with a flat surface is considered. The exact and approximate solution of the problem is presented. The exact solution has no restrictions on the external field configuration, physical properties of the medium, and frequency. The approximate solution is based on an expansion in asymptotic series and has limitations: for sinusoidal field, the solution is limited to frequencies above the lower limit; for pulsed field, the solution is limited by the initial time interval of the current pulse. Based on comparison of the results of exact and approximate calculations for nonuniform sinusoidal field at the interface between the media, the admissible value of the introduced small parameter is determined. For pulsed field the proposed choice of the limited time interval for calculating electomagnetic field using the asymptotic method is justified. References 29, figures 7.

Keywords

• three-dimensional electromagnetic field
• exact analytical method
• asymptotic series expansion
• skin effect
• sinusoidal and pulsed fields