If the high side of a delta-wye connected transformer is at 199 kV L-G high side voltage, what is the voltage across the winding of the delta transformer?

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To determine the voltage across the winding of the delta-connected transformer in a delta-wye configuration, it's essential to understand how the voltage transformation works in such a setup.

In a delta-wye transformer setup, the line-to-ground (L-G) voltage on the wye (Y) side is related to the line-to-line (L-L) voltage on the delta (Δ) side. The high side voltage given is 199 kV line-to-ground. When dealing with a wye connection, the relationship between line-to-ground voltage (Vg) and line-to-line voltage (Vll) on the wye side is expressed as:

[ V_{ll} = V_g \times \sqrt{3} ]

To compute the line-to-line voltage on the delta side, you take the line-to-ground voltage and multiply it by the square root of three. So, for a given high side voltage of 199 kV, the line-to-line voltage on the wye side is:

[ V_{ll} = 199 , \text{kV} \times \sqrt{3} \approx 345 , \text{kV} ]

In this case, the delta winding of the transformer would carry the same