Study on Advanced Maintenance Strategies and Asset Management for Substation Equipment in Japan: Investigation of the Transition of Substation Equipment Quantity, Trend Analysis of Failures

Abstract

Study on the advanced maintenance strategies and the asset management for the substation equipment is enthusiastically taken in place in Japan by the engineers from utilities and manufactures. This work is a part of the ETRA (Electric Technology Research Association) in Japan, where most of the Japanese utilities and manufactures cooperate with each other to address various issues that need to be improved or overcome for upwards of 80 years. The following working groups are organized in this study; “Investigation of the transition of substation equipment quantity, trend analysis of failures”, “Analysis of the degradation mechanisms of substation equipment and investigation of maintenance strategy”, “Investigation of recent technologies for advance maintenance strategies” and “Survey and research on asset management methods for strategic investment judgments”. Targeting substation equipment, this paper reports on a survey of the amount of equipment installed, its state of maintenance, and occurrence of failures, carried out by one of the four working groups. In pursuing the research, aimed at the advancement of maintenance, this survey was carried out on the amount of equipment installed, its state of maintenance and occurrence of failures, held by 11 utilities, which have installed such equipment in substations and switchyards. Concerning the amount of equipment and its state of maintenance, the working group carried out a survey of amounts of equipment at the end of each financial year for the equipment and period subject to such survey, as well as a survey of the state of patrols (items covered by patrol, patrol cycles, changes in cycles), and inspections (items covered by inspection, inspection cycles, changes in cycles) for equipment subject to such survey. Concerning the occurrence of failures, the working group carried out a survey of numbers of failures (by financial year, cause, parts of equipment affected, aspects, way of discovery, age of equipment, year of manufacture) which occurred in the equipment and period subject to such survey, together with correlations between failures ratios and state of maintenance.