INSULATION ABNORMALITY DIAGNOSTIC DEVICE, INSULATION ABNORMALITY DIAGNOSTIC METHOD AND PROGRAM FOR INSULATION ABNORMALITY DIAGNOSIS

摘要

PROBLEM TO BE SOLVED: To more exactly diagnose an insulation abnormality of an insulation object included in electric equipment without depending on installation environment of an acoustic sensor in the electric equipment.SOLUTION: An insulation abnormality diagnostic device comprises: a reference value calculation part 15 which calculates a reference value of intensity based on an intensity value representing the intensity of a signal for every frequency to be obtained by performing filter processing and envelope detection processing to an output signal of an acoustic sensor 10; and an index value calculation part 17 which calculates an index value for determining presence/absence of an insulation abnormality by calculating the intensity to the reference value for a signal of a frequency component which is n-times of a power frequency, and calculates a properly corrected index value so as to suppress an influence of variation of sound collection situations by installation environment of the acoustic sensor 10 by calculating the reference value from an acoustic signal actually detected at a site, and calculating the intensity of the signal to the reference value as the index value.