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A 3? power system consists of a Y-connected source (300 MVA, 23 kV) supplying a Y-connected...

A 3? power system consists of a Y-connected source (300 MVA, 23 kV) supplying a Y-connected load (240 MVA, 230 kV, PF = 0.90 lagging) through a step-up transformer (330 MVA, 23?/230Y kV, X = 0.11 per unit). Take into account the transformer’s phase shift and choose the load terminal voltage VAN as the reference. Use base values of 100 MVA and 230 kV at the load.

(a) Find the per-unit load currents (IA, IB, and IC).

(b) Find the per-unit source terminal voltage (Vt) and the per-unit source currents (Ia, Ib, and Ic).

(c) Find the real power supplied by the source (in MW) and the source power factor.

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