Transformer at Nho Quan 500kV Substation completely grid-separated in 20-day for the first time

After 15 years of operation at this particularly important node, the entire 500kV-450MW AT1 transformer of the Station is grid-separated for overhaul for the first time.

The AT1 transformer is manufactured by ALSTOM of France, which is one of the three main transformers at Nho Quan 500kV substation. The transformer has large capacity, located at very important node location, so the grid-separation for overhaul in many days is very difficult. This is the first time that the AT1 transformer has been de-energized for overhaul, after many periodical tests as per the process during 15 years of operation.

The Power Transmission Company No. 1 organized an overhaul with absolute safety for people and equipment. The overhaul concluded the removal of the bushing, change of the gasket, opening of the door for direct checking of main oil tank in thorough manner in order to detect the discharge points, aging insulation points, the transformer is dried with circulating oil combined with filtration, vacuum suction to separate water and impurities, etc.

The AT1 transformer will, after overhauled,  contribute to ensuring transmission reliability of the 500kV North - South power grid, particularly at the end of the year with many political, economic events and major festivals.

  • 11/12/2018 05:37