Ungrounded power TR in grounded network
Ungrounded power TR in grounded network
(OP)
Our contractor wants to install power transformer 110/20/6kV, Y,yn9,d11 in a substation. Primary (110kV) wounding of TR is not grounded. 110kV network is directly grounded.
Whats are the consequncies of connecting ungrouded primary in grounded network?
Whats are the consequncies of connecting ungrouded primary in grounded network?






RE: Ungrounded power TR in grounded network
Actually isn't problem, but you must check with your utilities. Point is, a ground fault level in this area.
For example only now, we installed two trafos 45/63MVA Y is ungrounded in 170kV grounded network. Reason is , installation is near ( 200-300m) to four big GSU ( 400 MVA) trafos.
Good Luck.
Slava
RE: Ungrounded power TR in grounded network
Regards
Marmite
RE: Ungrounded power TR in grounded network
RE: Ungrounded power TR in grounded network
Star point is isolated, is true. But grid is directly grounded.
You haven't overvoltages in case of ground fault. Of course if you haven't some islanding mode or your trafo is GSU.
Best Regards.
Slava
RE: Ungrounded power TR in grounded network