(Solved): So for part A, I got Is=391.3 A, Is,base= 521.74A, and Is,pu = 0.75. Is that correct? Can you als ...

So for part A, I got Is=391.3 A, Is,base= 521.74A, and Is,pu = 0.75. Is that correct?

Can you also explain how part B is solved with given equation and how the values used were found?

A 60-MVA 230/115-kV single-phase power transformer has a per-unit equivalent circuit as shown below. (a) If this transformer supplies a load of \( 45 \mathrm{MVA} \) at \( 0.85 \mathrm{PF} \) lagging, find per unit secondary current of the transformer after finding the secondary current and its base value. Note that base value of the secondary current is obtained by using the rated apparent power. HINT: The secondary current is given by \( I_{S}=\frac{S}{V_{S}}, I_{S, \text { base }}=\frac{S_{\text {base }}}{V_{S, \text { base }}} \) \[ I_{S, p u}=\frac{I_{S}}{I_{S, \text { base }}} \] (b) What is the voltage regulation (VR) of the transformer bank under the rated full load at \( 0.85 \) PF leading? Use per unit quantities. \[ \begin{array}{l} \text { HINTS: } \quad \mathrm{VR}=\frac{V_{P, p u}-V_{S, f l, p u}}{V_{S, f l, p u}} \times 100 \% \quad V_{S, f l, p u}=1.0 \\ \mathbf{V}_{\mathbf{P}}=\mathbf{V}_{\mathbf{S}}+\mathbf{I}_{\mathbf{S}} \mathbf{Z}_{\mathbf{e q}, \mathbf{S}} \end{array} \]