The uses of protection performance data within a transmission system

Data on power system protection equipment defects can be used to provide support for asset life predictions and the establishment of refurbishment, replacement, reconditioning and monitoring strategies. The requirement to compile protection fault performance and protection defect statistics therefore, has been established through the necessity to make protection policy and investment decisions on a rational basis. This paper describes the UK´s National Grid Company (NGC) system for collecting and analysing protection fault performance and defect data and provides illustrations of how the information is being used