A single-phase power system is shown as the equivalent circuit below. The system has a 480V generator connected to an ideal 1:10 step-up transformer (no losses), a transmission line, an ideal 20:1 step-down transformer and a load all in series as shown. The resistance of the transmission line is 20 S2 and the reactance j60 , a load is connected to the system with an impedance of 10/30° №. For the analysis of the system, use base values of 10 kVA and 480 V at the generator, find (a) per unit values of all impedances, (b) per unit current, (c) load power (W), (d) power loss (W). VG 480 0⁰ V 10 kVA Zone 1 1:10 20 Ω j60 Ω ZL Zone 2 20:1 ILoad Zone 3 ZLoad 10/30° Ω

A single-phase power system is shown as the equivalent circuit below. The system has a 480V generator connected to an ideal 1:10 step-up transformer (no losses), a transmission line, an ideal 20:1 step-down transformer and a load all in series as shown. The resistance of the transmission line is 20 S2 and the reactance j60 , a load is connected to the system with an impedance of 10/30° №. For the analysis of the system, use base values of 10 kVA and 480 V at the generator, find (a) per unit values of all impedances, (b) per unit current, (c) load power (W), (d) power loss (W). VG 480 0⁰ V 10 kVA Zone 1 1:10 20 Ω j60 Ω ZL Zone 2 20:1 ILoad Zone 3 ZLoad 10/30° Ω

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 3.26P: A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a...

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