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single-phase transformer question?

I need help figuring out this transformer question. I have no idea how to go about it and any information or help will be useful.A 100-kVA, 60-Hz, 7200-480 V, single-phase transformer has the following parameters expressed in OHMS:Rhs3.06 Rls0.014Xhs6.05 Xls0.027Xm,hs17,809 Rfe,hs71400The 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 loadc) The load component of high-side current;d) The input voltage to the transformere) the exciting current and its componentsf) the input impedance at no load

Answer:

A 100-kVA, 60-Hz, 7200-480 V, single-phase transformer has the following parameters expressed in OHMS: Rhs3.06 Rls0.014 Xhs6.05 Xls0.027 Xm,hs17,809 Rfe,hs71400 Primary winding is 15*N turns r 3.06 ohms in series with The primary leakage reactance which is L 16mhy(6.05 ohm @60Hz) in series with the magnetizing indctance Xm 17809 ohms 47.24hy which completes the primary series string the core loss is modelled as a 71.4k ohm resistor across the magnetizing inductance the secondary winding is 1*N turns R 0.014 ohms in series with the secondary leakage reactance is L 71.3UHy(0.027ohm@60Hz) the load draws 208.33A (100,000VA/480V) Z 2.304 ohms @ 48.6 deg 2.30448.6 1.786 ohms in series with +J 1.524 ohms(4.042mHy) (75% pf comes from voltage drop is seen from 2.304 ohms but only 75%(1.786 ohms) is resistive transfer from secondary to primary is done by multiplying impedances by 15^2 225 you should be able to do it from here.

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