A single-phase 100-kVA, 14/2.4-kV transformer connected to a source through a line impedance of 38.2 + j140 as shown in Figure 1. The transformer's equivalent series impedance referred to the secondary is 0.10+ j0.40 2. The load is 90 kW at 0.8 lagging power factor and 2300 V. V source Source 38.2 Ω j140 Ω www Feeder (transmission line) 010 Ω j040 Ω www Transformer Figure 1: Circuit for Problem 1 a) Find the voltage of the source. b) Find the voltage regulation of the transformer for this load. c) Find the efficiency of the transformer ignoring the core losses. Load Load 90 kW 0.80 PF

A single-phase 100-kVA, 14/2.4-kV transformer connected to a source through a line impedance of 38.2 + j140 as shown in Figure 1. The transformer's equivalent series impedance referred to the secondary is 0.10+ j0.40 2. The load is 90 kW at 0.8 lagging power factor and 2300 V. V source Source 38.2 Ω j140 Ω www Feeder (transmission line) 010 Ω j040 Ω www Transformer Figure 1: Circuit for Problem 1 a) Find the voltage of the source. b) Find the voltage regulation of the transformer for this load. c) Find the efficiency of the transformer ignoring the core losses. Load Load 90 kW 0.80 PF

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 3.4MCQ: An ideal transformer has no real or reactive power loss. (a) True (b) False

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