Chapter 3, Problem 3.49P

Consider the single-Line diagram of a power system shown in Figure 3.42 with equipment ratings given:

Generator $G_1$: $\text{50}\text{MVA,}\text{13}\text{.2}\text{kV},x=0.15\text{p}\text{.u}\text{.}$

Generator $G_2$: $\text{20}\text{MVA,}\text{13}\text{.8}\text{kV},x=0.15\text{p}\text{.u}\text{.}$

Three-phase $\text{Δ-Y}$ transformer $T_1$: $\text{80}\text{MVA,}\text{13}\text{.2}\Delta \text{/165YkV},X=0.1\text{p}\text{.u}\text{.}$

Three-phase $\text{Y-Δ}$ transformer $T_2$: $\text{40}\text{MVA,}165\text{Y/13}\text{.8}\Delta \text{kV},X=0.1\text{p}\text{.u}\text{.}$

Load: $\text{40}\text{MVA,}0.8\text{PF}\text{lagging,}\text{operating }\text{at}\text{150}\text{kV}$

Choose a base of 100 MVA for the system and 132-kV base in the transmission-line circuit. Let the load be modeled as a parallel combination of resistance and inductance. Neglect transformer phase shifts. Draw a per-phase equivalent circuit of the system showing all impedances in per unit.