Maintenance

Transmission networks, as engineered systems, can be maintained according to regimes with different levels of sophistication and corresponding implications for effectiveness and reliability (after P Birkner, 17th CIRED International Conference on Electricity Generation, 2003).

• Low sophistication: Corrective maintenance that will only react when failures occur
• Basic: Time-based maintenance or preventive maintenance of devices within fixed time periods
• Advanced: Condition based maintenance based on the results of a self-monitoring or a diagnostic system
• Sophisticated value-led: Reliability-centred maintenance that takes into account the functional importance of the device regarding service availability as well as its condition

When examining the record of modern cable-based systems, the key innovations in cables that have improved reliability and reduced the need for costly maintenance procedures are associated with jointing the lengths of cable together. These improvements have allowed transmission systems to receive benefits from the increased current-carrying capacity of cables. When an area of an overhead line network needs repair or essential maintenance, having cables in strategic areas of the system can assist in re-routing power to ensure continuity of supply.