Chapter 3, Problem 3.64P

The per-unit equivalent circuit of two transformers $T_a$ and $T_b$ connected in parallel, with the same nominal voltage ratio and the same reactan of 0.1 per unit on the same base, is shown in Figure 3.43. Transformer $T_b$ has a voltage-magnitude step-up toward the load of 1.05 times that of $T_a$ (that is, the tap on the secondary winding of $T_b$ is set to 1.05). The load is represented by $0.8+j0.6$ per unit at a voltage $V_2=\text{1}.0/0°$ per unit. Determine the complex power in per unit transmitted to the load through each transformer, comment on how the transformers share the real and reactive powers.