1. The resistances and reactances of a 25kVA 50Hz 2400:240V distribution transformer are R-0.650 £2, R2-0.00650 £2, X=7.0 £2, X2=0.070 £2, X=100 £2, where subscript 1, 2, / and M denotes the 2400V winding, 240V winding, leakage inductance and magnetizing (i.e., mutual) inductance, respectively. Each quantity is referred to its own side of the transformer. Core loss is negligible. Suppose a 240020°V power source is connected to the high-voltage side supplying transformer's rated KVA at 0.8 PF lagging. Draw the equivalent circuit referred to the low-voltage sides. Label the impedances numerically in ohms and henrys. b. Find the low-side terminal voltage phasor using the equivalent circuit in (a). Neglect the magnetizing branch. c. Find the equivalent circuit in per-unit. Use the rated power of the transformer as the power base. Include the magnetizing branch. d. Find the low-side terminal voltage phasor using the per-unit circuit in (c). Neglect the magnetizing branch.

Fig: 1