Remaining life diagnosis method and remaining life diagnosis device for electrical equipment

摘要

To solve a problem that actual measurement of an evaluation item related to lifetime of an electric appliance is necessary in a conventional insulation diagnosis, and that time and labor are required for electric power failure or local measurement.SOLUTION: A detection sensor for detecting an evaluation item which affects the deterioration of an insulator is installed in an electric appliance (S1). Next, a similar case is extracted from an actual result database in which information of an existing receiving and transforming apparatus is accumulated (S2). Surface resistivity at the time of setting the detection sensor is estimated from values of the similar case, and a relational expression of the number of years in use and the surface resistivity is obtained from the estimated value and the data of zero year in use (S3). Surface resistivity with respect to the number of years in use is sequentially calculated based on a base experimental database in which the correlation between the evaluation item and the surface resistivity is accumulated, the data obtained by the detection sensor, and S3 (S4). The number of life years is calculated from the correlation obtained in S4 and a predetermined threshold value (S5). The number of years in use of the electric appliance at the time of installation of the detection sensor is subtracted from the number of life years calculated in S5 so as to calculate the remaining lifetime (S6).SELECTED DRAWING: Figure 2