A 100kVA, 60Hz, 7200-480V, single-phase transformer has the following parameters expressed in ohms: Rhs=3.06 Rls=0.014 Xhs=6.05 Xls=0.027 Xm,hs=17,809 Rfe,hs=71,400.
The transformer is supplying a load that draws rated current at 480V and 75 percent power-factor lagging. Sketch the appropriate equivalent circuit and determine (a) the equivalent resistance and equivalent reactance referred to the high side; (b) the input impedance of the combined transformer and load; (c) the load component of the high current side; (d) the input voltage to the transformer; (e) the exciting current and its components; (f) the input impedance at no load.