Power Electronics - Engineering

Q1:

For a 12 pulse operation, the two 6 pulse units are fed by

A Y - Y and Y - Y transformers

B Δ - Δ and Δ - Δ transformers

C Y - Y and Y - Δ transformers

D Y - Δ and Y - Δ transformers

ANS:C - Y - Y and Y - Δ transformers

30° phase difference is necessary.