Transformer Vector Group for Power Transmission

Yes, so hire a consultant to help with it, Boss.

Expecting better Answer....

A schedule of charges, perhaps?

The first people to talk to would be the utility company. It won't be the first time they've turned round and said they don't want the site to export power. At the same time they will tell you if it's possible.

Expecting further better Answer....

Expect onwards.

Give a sincere try.....Boss

How much are you paying members of CR4 as consultants?

You are expecting an answer that is to your liking. In truth talking to the utility is the right answer, if they do not want to let you export your power you cannot do so, regardless of any technical information that you can provide.

PPA (Power purchae agreement) is in place with Utiliy. so export is no problem...

Answer please if can answer question asked,

Since you obviously know more about your situation than any of us care to know, why don't you tell us what your doubts are and why you think it won't work, and why you think vector group is even relevant in an already working situation; otherwise the answer still lies with your utility. Better yet, why don't you try it and see what happens.

System is commissioned and Importing power at the moment. Export is expected to start in 3 months with plant commissioning.

When Plant site importing power, transformer secondary at grid is earthed. so no problem. Any earth fault in interconnecting cable between Utility transformer and plant transformer would allow earth fault current through Zig-zag transformer and tripping source transformer.

When plant start to export transformer at plant site (11/33) would act as source and secondary is Delta.

What about protection for cable faults (Single phase to ground fault, etc). No return path for earth fault current to reach Delta connected secondary of transformer at plant site.

It's a bit late to start worrying about the consequences now, you're committed.

I doubt very much you will get any help from fellow members in the future.

One of the problems I see is - assuming your generators will be connected to 11kV bus, you need to have selection scheme between transformer neutral and generator (only one of generators will be earthed if more than one generator at 11kV bus) earthing.

You may have to go in for islanding protection to save generation (and the plant) in case of grid disturbances.

33kV cable 1-ph-ground faults cannot be supplied by the plant generation due the delta on 33kV side of 33/11kV transformer. This may not be a concern as the fault will still be supplied by the grid transformer and will be isolated as originally planned.

Hope the above is useful.

Happy singh:

As you have requested I have the answers you want:

1. The dog ran to the wet creek and plugged in the transmission line. addendum- Don't want to have anyone attempt to insult me so answer is coded.

2. The dog ran back from the CR4 insane asylum to develop respectful answer for electrical engineering at 33KV SWGR 59v or 20% Addendum- This also is an attempt to not have anyone try to insult me so answer is coded.

In Summary- "You can catch more flies with sugar than you can with vinegar." (Famous quote from the distinguished chemist, Wiley T. Coyote) Interpretation- You can get many more good answers, like my disguised one is, with cooperation than you can with sarcasm. Interpretation of Interpretation- Lay off the Acetic Acid and cooperate and you will get my good answer and a lot of others like it.

Good Luck, Old Salt

Give it a real try.... and it is not coded