choosing the transformer vector group
choosing the transformer vector group
(OP)
Hi,
all the transformers in a subtransmission network are Dyn11, in another part of the network a transformer with the vector group of YNd1 is going to be used for an industrial complex .there is no chance of paralleling of transformers but the primary of them are all connected in a ring of 132 KV.is there any hidden problem in choosing the YNd1 vector group? or should all the transformers be selected to be Dyn11?thanx
all the transformers in a subtransmission network are Dyn11, in another part of the network a transformer with the vector group of YNd1 is going to be used for an industrial complex .there is no chance of paralleling of transformers but the primary of them are all connected in a ring of 132 KV.is there any hidden problem in choosing the YNd1 vector group? or should all the transformers be selected to be Dyn11?thanx






RE: choosing the transformer vector group
RE: choosing the transformer vector group
the industrial complex is radial
RE: choosing the transformer vector group
I do not think there are any technical issues if you are not parllelling. Share your comments
RE: choosing the transformer vector group
If the primary of the Ynd1 transformer is grounded, it will be a ground source and could affect ground protection.
RE: choosing the transformer vector group
RE: choosing the transformer vector group
Zero-sequence elimination will prevent transformer differential operation for the external fault, but you probably also have overcurrent relays. I'm not saying that you can't use the connection, just that the ground source has to be considered.
RE: choosing the transformer vector group
RE: choosing the transformer vector group
I agree with jghrist and mgtrp.
Think of the delta connection as two parts. A phase and B phase forming an open delta and C phas as a single phase transformer.
If the voltage is high or low on C phase, there will be a voltage error when it is connected across the open delta. Expect high circulating currents.
If you lose C phase the single transformer will be back fed and try to supply the loads on the missing phase. If C phase is grounded on the primary, the C phase transformer will still back feed and contribute to the fault current.
There are other effects on the primary side also.
Bill
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"Why not the best?"
Jimmy Carter
RE: choosing the transformer vector group
RE: choosing the transformer vector group