A 20-kVA, 8000:480-V distribution transformer has the following resistances and reactances: Rp=32 ohm Rs=0.05 ohm Xp= 45 ohm Xs = 0.06 ohm Rc=250,000 ohm XM= 30,000 ohm The excitation branch...

Extracted text: A 20-kVA, 8000:480-V distribution transformer has the following resistances and reactances: Rp=32 ohm Rs=0.05 ohm Xp= 45 ohm Xs = 0.06 ohm Rc=250,000 ohm XM= 30,000 ohm The excitation branch impedances are referred to the high-voltage side. a) Find the equivalent circuit of the transformer referred to the high- voltage side. b) Find the per unit equivalent circuit of this transformer. c) Assume that the transformer is supplying rated load at 480 V and 0.8 power factor lagging. What is this transformer's input voltage? What is its voltage regulation? d) What is this transformer's efficiency under the conditions of part (c)? 57 EMI Transformers Dr Thamir Hassan ATYIA Tikrit University