Power System Analysis and Design (MindTap Course List)
6th Edition
ISBN: 9781305632134
Author: J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma
Publisher: Cengage Learning
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Textbook Question
Chapter 7, Problem 7.3MCQ
The amplitude of the sinusoidal symmetrical ac component of the three-phase short-circuit current of an unloaded synchronous machine decreases from a high initial value to a lower steady-state value, going periods through the stages of __________ and ________ periods.
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Q-5-) 60 Hz generator supplies 0.50 Pmax power to a busbar with infinite power over a conveying line.
When a fault occurs, the reactance value between the generator and the infinite bus becomes 400% times
the value before the fault. When the fault is isolated, the maximum power that can be transferred
generator to the endless bus is 75% of the original (initial) maximum value. Accordingly, using t
area criterion method, calculate the critical clearance angle of the system.
00
Figure shows a generator connected to a metropolitan system (infinite bus) through highvoltage lines. The numbers on the figure indicate the reactances in p.u. Breakers adjacent to afault on both sides are arranged to clear simultaneously. Determine the critical clearing anglefor the generator for a 3-phase fault at the point P when the generator is delivering 1.0 p.u.power. Assume that the voltage behind transient reactance is 1.2 p.u. for the generator andthat the voltage at the infinite bus is 1.0 p.u.
The __________________ condition of the power system gives the power flow solutions when the transient behavior of the system is to be studied.
a-Initial
b-Short Circuit
c-Stability
d-Transient
Chapter 7 Solutions
Power System Analysis and Design (MindTap Course List)
Ch. 7 - Even though the fault current is not symmetrical...Ch. 7 - The amplitude of the sinusoidal symmetrical ac...Ch. 7 - Equipment ratings for the four-bus power system...Ch. 7 - Equipment ratings for the five-bus power system...Ch. 7 - Prob. 7.22PCh. 7 - A three-phase circuit breaker has a 15.5-kV rated...Ch. 7 - Prob. 7.32P
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