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So I'm doing a delta wye transformer simulation in simulink, and I need some clarification about transformer voltages. Here's a image from a youtube video Delta wye transformer

We have phase voltages on primary that are 4160 V, but we also have Voltage A to ground, B to ground and C to ground which is 2400 V.

And on the secondary side when we will look for a phase shift we are going to look for a to ground, b to ground, and a to ground voltages that are 480 V.

So my question is when we have a transformer (delta-wye) for example 220kV/110kV, so primary voltage is 220kV, but what voltage is it, voltage A to ground(VAG in video) or phase A (VAB)?

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So my question is when we have a transformer (delta-wye) for example 220kV/110kV, so primary voltage is 220kV, but what voltage is it, voltage A to ground(VAG in video) or phase A (VAB)?

The default voltage specified for a three phase system is line voltage irrespective of the type of transformer that connects to it. So, if it is specified as 11 kV then that is the RMS voltage between power lines and will only be the phase voltage if it explicitly mentions that it is a phase voltage.

We have phase voltages on primary that are 4160 V

That is a misnomer; the voltage between two power lines in a three phase system is called line voltage not phase voltage.

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  • \$\begingroup\$ Also on the primary in the diagram, there is no ground or neutral, so the phase to ground voltage is not really defined. However the source that is feeding the primary may be the wye secondary of another transformer with a grounded neutral. The voltage to neutral would be 2400 volts at that point, but it could be some distance away. \$\endgroup\$
    – user80875
    Commented Jan 26, 2020 at 16:59

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