Question

A 33 kV, three-phase, 50 Hz line of resistance 2 Ω/ph and
reactance j9 Ω/ph supplies a 33 kV/440 V transformer having
negligible resistance and reactance of j2 Ω/ph referred to 33 kV.
The transformer supplies a 440 V feeder of resistance 0.01 Ω/ph and
reactance j0.007 Ω/ph. If V_{R}, the receiving-end voltage,
is 440 V, calculate V_{S}, the sending-end voltage, when
the three-phase load delivered is 440 kW at unity power
factor.

Answer #1

Use MATLAB:
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