In this article, a closed-form expression for the impedance of a tangential eddy-current coil
in the presence of an infinite conducting wedge of arbitrary angle is derived. The truncated
eigenfunction expansion (TREE) solution given here is valid in the quasi-static frequency
regime. The theory was validated via comparison to an independent analytical expression
for the impedance change of a horizontal coil over a conducting half-space due to Burke.
We present results for three geometries: a conducting quarter-space, a conducting wedge of
angle 225 degrees, and a semi-infinite conducting sheet. Our theory predicts a measurable
change in the tangent coil reactance in the presence of all three geometries.
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