Target Temperature Effect on Eddy-Current Displacement Sensing

Target temperature effect on eddy current displacement sensing is analyzed and evaluated by simulation. The equivalent target quality factor is detected as the main factor that, along with the probe equivalent quality factor, determines this effect. It manifests in ambiguity of displacement measurement, as well as, masking the displacement variation by target temperature variation, and vice versa. The analysis and the simulation show that there is an optimal operating frequency for minimum sensitivity over an acceptable displacement range.