Inductance-change detection apparatus

摘要

The inductance-change detection apparatus comprises an inductance-change converter that converts inductance-change in coils into voltage to output, a reference-voltage generator that generates and outputs a predetermined reference voltage, a frequency characteristic adder that adds a frequency characteristic similar to that of the converted voltage converted by the inductance-change converter to the reference voltage, a reference-voltage compensator that varies and compensates the frequency spectrum of the reference voltage containing the added frequency characteristic, in parallel in the direction of amplitude, corresponding to a parallel variation of the frequency spectrum of the converted voltage in the direction of amplitude, and an inductance-change detector that compares the converted voltage with the compensated reference voltage to detect inductance changes in the coils.