De-risking the implementation of real-time thermal ratings

This paper addresses the de-risking of real-time thermal ratings (RTTRs) for overhead lines to help build DNO business confidence in the adoption of the technology. Through the use of thermal state estimation with integrated sensors and graceful degradation algorithms, a cost-effective RTTR system is being implemented across the 132kV network in North Wales. The system unlocks significant energy yields (up to 14,358 MWh in November 2012 for a single overhead line circuit) whilst minimising the risk of line temperature profile exceedence to a suitably low value.