Will it be OK to connect a 5MVA 33/6.6kV Ynd11 Transformer to a Star connected

Will it be OK to connect a 5MVA 33/6.6kV Ynd11 Transformer
to a Star connected Motor. Or on other words connecting a
Delta to a Star.

I have another 30MVA 33/11 Dyn11 and would it be practical
to convert it to Dd0 consequently converting the Voltage
Ratio to 33/6.35kV Dd0.

Question Posted / fahri

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Will it be OK to connect a 5MVA 33/6.6kV Ynd11 Transformer to a Star connected Motor. Or on other w..

Answer / a.p.nanjappa

yes. what is the capacity of motor?
In your case , grid voltage is 33kv, Yn connected.Hence
power transformer has neutral connection brought
out.Neutral CT is installed to detect the ground faults.
secondary of 5MVA tranformer is 6.6kv,
This is Feeder bus voltage.6.6kv Feeder bus feeds Motor (
star connected). and Feeder bus is not interconnected to
another source. It is independent.This 6.6kv rotates at 30
lagging to primary3kv system.
Motor must be use inverse & instantaneous time
overcurrent and earth fault ( CDG61+cdg12) or equivalent
manufacturer protection
we use delt to star as weelas star 6.6motor.
No problems experienced.
In the othercase to change a 30MVA,33/6.35KV IS
REDESIGN/MANUFATURING. iT IS EXPENSIVE.No use at all and
advantage. You should change 6.6kv sw.gr also.