Tales of Wind #4 - Nordex – Transformer replacement

LV/MV turbine transformers are critical components in wind turbines. They are essential for the production of a wind turbine and preventive checks need to be carried out before any damage occurs. If a transformer is not functional, it is the whole turbine that can be put on stop for the duration of the replacement, which can be a potentially long period considering the heavy works with the implication of cranes and landscape works that could be necessary.

Some issues like partial discharge problems may not be visible and may be internal to electrical equipment. The only way to identify the location of the fault and the origin is using ultrasound. Partial discharge type defects can cause significant damage to equipment such as transformers, MV switchboards, MV cable ends and lead to fires in electrical installations.
During a simple visual inspection led in 10/2023 on an N80 Wind farm, abnormal noises were detected by Greensolver near the MV/LV transformers of turbines. This issue was raised to Nordex, that carried out their own visual inspection without any specific findings.

Greensolver pushed the subject forward and carried out an ultrasound inspection in 04/2023 which showed evidence of issues on 3 turbines : partial discharge and evidence of vibrating parts. With those additional inputs, Nordex carried out the replacement of a transformer. The duration of the stop was the duration of the works only. There was no downtime due to unexpected damage of the transformer because the first signs of damages had been found early enough.

Greensolver is proactive into findings early signs of damages and prevent extended downtime periods due to major components replacements.

Written by Technical and Financial Asset Management Team