The Corona Effect on Transmission Lines

COTESA Engineering has concluded the detailed inspection with escalation of 137 metallic structures, with grounding resistance measurement, thermographic verification and corrective maintenance.

The Transmission Line, which is more than 50km long, has a simple circuit and one conductor cable per phase. During the thermographic inspection no abnormality was identified, having inspected the splices of the conductor cables, at the exit and arrival of the substations.

However, during the climbing inspection, a large number of loose, hanging and dented parts were detected, compromising the integrity of the structure. Anomalies were also identified in the insulator chains, such as signs of atmospheric discharge, misaligned discs and missing or poorly positioned cotter pins at the bottom. 

COTESA Engenharia is responsible for the O&M of 7 thousand km of Transmission Lines and 117 substations connected to the National Interconnected System.