Vector Group

Since all the transformers are of the same capacity and same make, what is left is the same vector group.These transformers should have the same values in all their parameters so that they will share the load equally.

Since This is an independent grid separate from the main grid and no othe inputs to it, I don't see why the vector group should be specific: All you need is to have all the transformers with the same vector group.

LAA. The best performing vectors group for all delta wound transformer is D/D-0 & D/D-6. D/D-11 or D/D-1 will also work but it is best for D/Y transformers.

The issue of having the same ratings of transformer does not count. The transformers can be of different ratings, the important issue here is; they must be of same vector group. The individual transformer through their RMUs and protective breakers deliver their power to the High voltage bus. Issues of rating are handled by this protective breaker and RMU.

Ur free to select any vector group that satisfies Ur want. The important thing is all the transformer you are using must belong to the same vector group.

In your case precisely groups 1 & 11 are ruled out, U have to select any of the remaining two groups( 0 or 6 ) for Ur project.

DICKSON.

The standard vector groups used are 1, 5, 11 but all the others from 0 to 11 are available if requested or ...

can you please say why in his case 1 and 11 are ruled Out?

Also, Normally, if from a generator to a grid, you use Start to Delta to allow a transmission with 3 wires only.

The only restriction here is that all the transformers must have the same vector group (apart from the other parameters stated before). Can you please elaborate and Thanks.