A hydro powered 50 MVA generator, with a synchronous reactance 0.33 p.u., delivers 40 MW over a transmission line of 0.15 p.u. reactance to an infinite system. A 3-phase short circuit transient fault occurs on the busbar between the generator and transmission line. Given that the generator emf is 1.4 p.u. prior to and during the fault and all reactances are to a 50 MVA base: Sketch the single line schematic diagram of the system. Determine the maximum load angle the generator can swing to without losing stability i) ii)

A hydro powered 50 MVA generator, with a synchronous reactance 0.33 p.u., delivers 40 MW over a transmission line of 0.15 p.u. reactance to an infinite system. A 3-phase short circuit transient fault occurs on the busbar between the generator and transmission line. Given that the generator emf is 1.4 p.u. prior to and during the fault and all reactances are to a 50 MVA base: Sketch the single line schematic diagram of the system. Determine the maximum load angle the generator can swing to without losing stability i) ii)

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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Concept explainers

Synchronous Generator

In comparison to an asynchronous generator, it is a machine where the rotor speed is equal to the rotating magnetic field produced by the stator, i.e., mechanical speed is equal to the electrical speed, thus called synchronous, and not asynchronous.

Salient Pole Rotor

Salient pole rotor includes a large number of exposed poles mounted on a magnetic wheel. The construction of a bright pole is as shown in the image on the left. The proposed poles are made of metal laminations. The rotor winding is provided on these poles and is supported by pole shoes.

Question

A hydro powered 50 MVA generator, with a synchronous reactance 0.33 p.u.,
delivers 40 MW over a transmission line of 0.15 p.u. reactance to an infinite
system. A 3-phase short circuit transient fault occurs on the busbar between
the generator and transmission line.
Given that the generator emf is 1.4 p.u. prior to and during the fault and all
reactances are to a 50 MVA base:
Sketch the single line schematic diagram of the system.
Determine the maximum load angle the generator can swing to without
losing stability.
i)
ii)
iii)
iv)
Sketch the corresponding power-angle curve for the system showing
the accelerating and decelerating areas.
Calculate the critical clearing angle of the system to keep its stability.

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