A guideline for optimizing outage management of Eskom's transmission network

Abstract

A streamlined process is needed to optimize the outage management of the Eskom transmission power system, as well as a ranking system in order to determine the best window of opportunity for an outage to occur thus positively impacting on Eskom‘s asset management. The outage data captured between 2007 and 2011 was analysed for all cancelled, turned down and completed outages. This data indicated that there were 19 902 completed outages, 5 312 cancelled outages and 1 889 turned down outages in the 5 years. These numbers increase Eskom‘s costs in terms of resources and risks to system security. The reasons for the cancelled and turned down outages were investigated, while the completed outages were further broken down into transformer, reactive devices and line outages. For the cancelled and turned down outages, it was ascertained that should the suggested changes occur in the form of better training and communication, the cancelled outages can be reduced by up to 11% while the turned down outages may be reduced by 2.5%. A guideline for a maintenance plan, based on the manufacturers‘ specifications was suggested and implemented on the historic 5 year data in order to determine if the outage numbers could be reduced. This proved to be effective, as the transformer outages could be reduced by 40%, the reactive devices reduced by 36% and the line outages could be reduced by up to 60%. A ranking system was also developed in order to assist maintenance planning by suggesting a window of opportunity for the outages to take place.