ESTIMATION METHOD OF COPPER SULFIDE GENERATION STATE OF OIL-FILLED CABLE BY INSULATION OIL ANALYSIS, AND DIAGNOSTIC METHOD OF RISK DEGREE

摘要

PROBLEM TO BE SOLVED: To provide a diagnostic method of estimating a sulfide generation state in an oil-filled cable using an insulation oil and estimating a degree of risk of abnormality occurrence of the oil-filled cable based on the sulfide generation state estimated by the method.;SOLUTION: An estimation method of a copper sulfide generation state of an oil-filled cable includes: a step 1 of preparing a trend graph showing a change with time of a dissolution amount of copper in oil or dielectric loss tangent and a total amount of combustible gas; a step 2 of preparing a graph showing a relationship between the dissolution amount of copper in oil of an insulation oil collected from the insulation oil before using the oil-filled cable and the oil-filled cable and obtaining the maximum dissolution amount of copper in oil from the value of the maximum dielectric tangent in the past; and a step 3 of obtaining a ratio of the dielectric tangent to the amount of the dissolution copper in oil. The generation state of sulfide copper in the cable is estimated by using the values of steps 1 to 3. In addition, a degree of risk is estimated and diagnosed based on a ratio of the dielectric tangent obtained at the step 3 to the dissolution amount of copper in oil, the reference value of the maximum dissolution amount of copper in oil, and the reference value of the total amount of the combustible gas.;SELECTED DRAWING: Figure 5;COPYRIGHT: (C)2017,JPO&INPIT