A 10-kVA, 450/120V, 50-Hz transformer has the following circuit parameters: R, = 0.12 n, R, = 8.533 mn, X, = 0.18 N, X, = 12.8 mn R = 2530 n, Xm = 409 N %3D Using the modified equivalent circuit of transformer referred to secondary as shown in the figure below The load of the transformer has unity power factor at rated load. Determine: (a) primary voltage referred to secondary, V,' (b) no-load primary current referred to secondary, I,' (c) primary current referred to primary, I,' (d) input impedance referred to secondary, Zn (e) percent voltage regulation at UPF referred to secondary, %VR' (f) input power factor referred to secondary, p.f.n' (8) input power referred to secondary, Pn' (h) percent efficiency of the transformer at UPF referred to secondary, %n' al, - i,' Res Xes İs %3D al. alY al, Es = Eda Vs Z. %3D R Xm a? a?

A 10-kVA, 450/120V, 50-Hz transformer has the following circuit parameters: R, = 0.12 n, R, = 8.533 mn, X, = 0.18 N, X, = 12.8 mn R = 2530 n, Xm = 409 N %3D Using the modified equivalent circuit of transformer referred to secondary as shown in the figure below The load of the transformer has unity power factor at rated load. Determine: (a) primary voltage referred to secondary, V,' (b) no-load primary current referred to secondary, I,' (c) primary current referred to primary, I,' (d) input impedance referred to secondary, Zn (e) percent voltage regulation at UPF referred to secondary, %VR' (f) input power factor referred to secondary, p.f.n' (8) input power referred to secondary, Pn' (h) percent efficiency of the transformer at UPF referred to secondary, %n' al, - i,' Res Xes İs %3D al. alY al, Es = Eda Vs Z. %3D R Xm a? a?

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.12P

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A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary winding, absorbs 60 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the following: (a) primary voltage, (b) load impedance, (c) load impedance referred to the primary, and (d) the real and reactive power supplied to the primary winding.
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