MURILLO
Nuclear
- Aug 5, 2005
- 7
Hi colleagues,
Actually we have a 3 bank power transformer with the following data sheets:
3 x 420 +-2.5+-5% kV / 20 kV
YNd11
3x420MVA - OF AF
The 87TG protection has conected an old design (dated from 1970) to compensate the homopolar component in the low voltage side, that include three CT in every winding phase conected in parallel and an auxiliary CT open delta / Wye used to conect to the 87 relay. Does anybody know this way to compensate the homopolar component ? Has anybody references about it?
The point is that now we are working to replace this relays and the actually digital differential transforme relay has features to filter the secuence zero component (on high voltage side) and this complex circuit shouldn't necesary.
Thanks
Actually we have a 3 bank power transformer with the following data sheets:
3 x 420 +-2.5+-5% kV / 20 kV
YNd11
3x420MVA - OF AF
The 87TG protection has conected an old design (dated from 1970) to compensate the homopolar component in the low voltage side, that include three CT in every winding phase conected in parallel and an auxiliary CT open delta / Wye used to conect to the 87 relay. Does anybody know this way to compensate the homopolar component ? Has anybody references about it?
The point is that now we are working to replace this relays and the actually digital differential transforme relay has features to filter the secuence zero component (on high voltage side) and this complex circuit shouldn't necesary.
Thanks