State any two conditions for parallel operation of 3-phase transformer.

State any two conditions for parallel operation of 3-phase transformer.
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1 Answer

Answer :

Conditions for Parallel operation of 3 phase transformer

1) Voltage ratings of both the transformers must be identical.

2) Percentage or p.u. impedance should be equal in magnitude.

3) X/R ratio of the transformer winding should be equal.

4) Transformer polarity must be same.

5) Phase displacement between primary & secondary voltages must be same.

6) Phase sequence on both sides must be same.
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