Multi-system overhead lines inspections - The experience of LABELEC with EDP Distribution lines

The long experience of LABELEC in airborne infrared (IR) and visual inspections of EDP Distribution overhead electric lines (OHL) is now enriched with the possibility of measuring and localising abnormal clearances between cables and trees or other obstacles. This was achieved using a Laser-Global Positioning System (GPS) solution that started being developed in LABELEC and later on was set ready for operation by Albatroz Engineering. Previously, some experimental track clearances measurements were carried out in distribution OHL, using high-quality but high-cost airborne-topography equipments. Now, the IR detected hotspots and visible anomalies information can be complemented with sufficiently accurate track clearances and its GPS information, using Albatroz system, with only a small increase in operational costs. The three types of inspection can be performed with a single flight over the transmission or distribution lines, using a medium operational cost helicopter like the Eurocopter Colibri EC 120 B. The near future may bring the integration of corona effect detection and visualisation into LABELEC multi-system OHL inspections, further contributing to a higher level of efficiency in lines maintenance activities.