Problem 3.5: From a 3-phase, 480 V generator switchboard, a feeder takes 3-phase power to two equipment at the other end via cable and trans- former with the combined series impedance Z = 0.04 + j 0.09 2 per phase. The voltage at receiving end point A rises and falls as a large 3-phase, 500 kVA load at point A varies over time. The small 1 kVA load, also connected at point A, remains online continuously, and must accommodate the voltage variations at point A with the 500 kVA load fully on or fully off. Determine the voltage range that the 1 kVA load will see, over which it must perform within its specifications.

Problem 3.5: From a 3-phase, 480 V generator switchboard, a feeder takes 3-phase power to two equipment at the other end via cable and trans- former with the combined series impedance Z = 0.04 + j 0.09 2 per phase. The voltage at receiving end point A rises and falls as a large 3-phase, 500 kVA load at point A varies over time. The small 1 kVA load, also connected at point A, remains online continuously, and must accommodate the voltage variations at point A with the 500 kVA load fully on or fully off. Determine the voltage range that the 1 kVA load will see, over which it must perform within its specifications.

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

Chapter8: Symmetrical Components

Section: Chapter Questions

Problem 8.6P

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