Ukrenergo performed complex repair works on a 40-meter high metal 750 kV high-voltage pole in Pivnichna power system. The emergency disconnection of 750 kV ultra-high-voltage overhead line (OHL) “Pivdenno-Donbaska – Donbaska” happened on 27 December because of the damages caused to two cables and a part of the crossarm of a 40-meter intermediate pole.
Under complicated weather conditions, the company’s employees replaced the crossarm’s console – a massive cross bar an insulator string is attached to.
First of all, electricians and welders dismantled and cut the damaged console off the crossarm at the height of 32-35 m. At the same time, Bakhmutskyi repair and operation centre produced a new console. The console’s elements were marked, dismantled and then assembled once again directly on the pole.
A console of 70 elements had to be assembled at the height of more than 30 metres. The length of separate parts of the console reached around 10 metres, while the total weight of the structure exceeded 1 tonne.
All these works were completed within very short terms given the level of complexity – within three days.
The severity of the situation was amplified by the fact that the damages to the network could have turned to badly affect the whole power system, in particular, restrict the capacity output of Zaporizhzhya NPP by approximately 300 MW and reduce consumption in Mariupol power knot. We would have had to compensate for the deficit in capacity at the expense of other types of generation, in particular the manoeuvring capacities of coal-based TPP. At the same time, taking into account the existing reserves of coal at TPPs, it would be unacceptable.
Thanks to the bravery and professionalism of Ukrenergo’s employees, we managed to restore the reliability of power supply in the region and prevent any emergency outages.