Hi all, this will be my first post here in this forum. I really need some help regarding High Voltage equipment, and i'll be grateful to anyone who can assist.
I am considering earthing a corner of a delta connected 66kV tertiary winding of a 400kV Transformer. However, I am told that this will raise the potential of the other phases in the tertiary winding with respect to earth. I need someone to explain why this is so, as I can't seem to figure that out.
In addition, the BIL for the tertiary winding is said to increase from 350kV to 450kV. Can someone help to explain this? If the transformer is situated indoors and connected to underground cables rather than overhead lines, is there a need to comply with this increase in BIL requirement?
It would be best if anyone can help point out any reference material that will assist in understanding why these things are so.
I am considering earthing a corner of a delta connected 66kV tertiary winding of a 400kV Transformer. However, I am told that this will raise the potential of the other phases in the tertiary winding with respect to earth. I need someone to explain why this is so, as I can't seem to figure that out.
In addition, the BIL for the tertiary winding is said to increase from 350kV to 450kV. Can someone help to explain this? If the transformer is situated indoors and connected to underground cables rather than overhead lines, is there a need to comply with this increase in BIL requirement?
It would be best if anyone can help point out any reference material that will assist in understanding why these things are so.