Current distribution in circular planar coil

The current distribution over the cross section of a planar circular coil is calculated by a Fredholm integral equation technique. An external applied current source is driving the current. The integral equation technique is applied over a two-dimensional cross section of the coil while considering infinitesimally thin windings. The coil windings are divided into equally sized one-dimensional elements. The resulting algebraic system is solved numerically. For low frequencies, the current distribution follows the 1/r behavior. As the frequency increases, the influence of the proximity effect is taken into account. Different cases are studied examining the intensity of these effects on the current distribution as the number of turns, the width of the windings, and the spacing between the turns are varying.