A three-phase system includes a 346.4 V line-to-line supplying a three-phase motor rated 15KVA 0.8pf lag plus additional balanced constant impedance loads. The single-phase representation of the system is shown below. Assume that sources and loads are Y-connected. 1. What is the RMS value of the line current, I in A? 2. If this set of loads will be supplied through a service transformer. What should the minimum size of the transformer in kVA? 3. What should be the size of three-phase capacitor(that will be added to the load mix) to improve power factor to almost 0.95 lag?

A three-phase system includes a 346.4 V line-to-line supplying a three-phase motor rated 15KVA 0.8pf lag plus additional balanced constant impedance loads. The single-phase representation of the system is shown below. Assume that sources and loads are Y-connected. 1. What is the RMS value of the line current, I in A? 2. If this set of loads will be supplied through a service transformer. What should the minimum size of the transformer in kVA? 3. What should be the size of three-phase capacitor(that will be added to the load mix) to improve power factor to almost 0.95 lag?

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

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.2P: Convert the following instantaneous currents to phasors, using cos(t) as the reference. Give your...

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