QUESTION 1 Figure Q1 shows a single-line diagram of an 8-bus system. Line-1 and Line-2 have reactance 10 Q and 15 2, respectively. The data of generator, transformers, and motor are given in Table Q1(a). The three-phase Load-1 at bus-4 absorbs 35 MVA, 0.7 lagging at 11 kV, while the three- phase Load-2 at bus-8 absorbs 15 MVA, 0.8 lagging at 11kV. a) Sketch an impedance diagram with all impedances including the load impedance marked in per-unit. Select a common base of 100 MVA and 23kV on the generator. b) The motor on the Figure Q1 operates at 36.28MVA on a lagging power factor 0.9 at a terminal voltage of 10.45 kV. Determine the voltage at bus-5 in per-unit and kV. c) Evaluate the voltage obtained in Question (b) either at the acceptable voltage range or not? You may use Table Q1(b) as reference.

QUESTION 1 Figure Q1 shows a single-line diagram of an 8-bus system. Line-1 and Line-2 have reactance 10 Q and 15 2, respectively. The data of generator, transformers, and motor are given in Table Q1(a). The three-phase Load-1 at bus-4 absorbs 35 MVA, 0.7 lagging at 11 kV, while the three- phase Load-2 at bus-8 absorbs 15 MVA, 0.8 lagging at 11kV. a) Sketch an impedance diagram with all impedances including the load impedance marked in per-unit. Select a common base of 100 MVA and 23kV on the generator. b) The motor on the Figure Q1 operates at 36.28MVA on a lagging power factor 0.9 at a terminal voltage of 10.45 kV. Determine the voltage at bus-5 in per-unit and kV. c) Evaluate the voltage obtained in Question (b) either at the acceptable voltage range or not? You may use Table Q1(b) as reference.

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

Chapter5: Transmission Lines: Steady-state Operation

Section: Chapter Questions

Problem 5.37P

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