A 30-kVA, 8000/230-V distribution transformer has impedance referred to the primary of 20 + j100 N. The components of the excitation branch referred to the primary side are Rc = 100 kN and Xm = 20 kQ. (a) Draw the approximated equivalent referred to the primary side. (b) If the primary voltage is 7967 V and the load impedance is ZL = 2.0 +j0.7 N, what is the secondary terminal voltage of the transformer? What is the voltage regulation of the transformer? (c) If the load is disconnected and a capacitor of -j3.0 Q is connected in its place, what is the secondary voltage of the transformer? What is the voltage regulation under these conditions?

A 30-kVA, 8000/230-V distribution transformer has impedance referred to the primary of 20 + j100 N. The components of the excitation branch referred to the primary side are Rc = 100 kN and Xm = 20 kQ. (a) Draw the approximated equivalent referred to the primary side. (b) If the primary voltage is 7967 V and the load impedance is ZL = 2.0 +j0.7 N, what is the secondary terminal voltage of the transformer? What is the voltage regulation of the transformer? (c) If the load is disconnected and a capacitor of -j3.0 Q is connected in its place, what is the secondary voltage of the transformer? What is the voltage regulation under these conditions?

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 3.4P: A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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