Twelve years of Live Substation Work at Powerlink Queensland Australia

Abstract

This presentation explains why Live Work was introduced in Powerlink substations in 2001 and how it has been used since. One measure of the performance of a transmission network resides with the reliability of both substation and line assets. Live Work on line assets is a mature practice that network owners have invested in to minimise interruptions to critical circuits. Powerlink's implementation of Live Work practices on substation plant provides a holistic approach to reliability and availability across the entire transmission network. Limited proven methodologies for Live Work in substation practices were available for evaluation considering the preferred option was an adaptable and safe approach based on specific risk analysis. Reseau de Transport d'Electricite's (RTE's) approach for Live Work in substations met Powerlink's requirements with regard to risk analysis as it uses a specific analysis for each task and environment. Performing Live Work tasks in a safe manner is dependent on using and applying suitable methods and tools and meeting general safety regulations and specific Live Working Conditions manual. The core of the Live Work Conditions manual was initially drawn up by RTE (SERECT; Service dedicated since 1962) which develops and markets specific tools according to the warranted characteristics presented in their Technical Sheets. At Powerlink, Live Work Hotstick and Barehand methods have been used safely and without incident for 12 years. With 14,000 hours of Live Work performed yearly, the Live Substation Team has 10 operators/team leaders accredited by Powerlink to perform Live Work. Live Substation Work is often selected as the preferred method for project and maintenance tasks for the 126 substations Powerlink has across Queensland. As a demonstration of Live Work skills and know-how, Powerlink presents a complex Live Work job at Tarong Substation: The objective was to increase the capacity of the 275 kV switchyard by installing additional bus-bar lengths in parallel to the existing buses in a vertical configuration. All operations involved the Live Substation Team, whilst maintaining the whole 275 kV switch yard operational; i.e. without any outages to the 275 kV buses and feeders and all tasks carried out under Live Work rules. The additional bus-bars have been put in place using crimped joints with welded tags. In total, the Live Substation Team carried out the placement of 48xlO m long bus-bars (totaling 480 m of bus length).