Electric machinery fundamentals
5th Edition
ISBN: 9780073529547
Author: Chapman, Stephen J.
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Chapter 6, Problem 6.1P
(a)
To determine
The value of the speed of the magnetic fields in revolutions per minute.
(b)
To determine
The value of the speed of the rotor in revolutions per minute.
(c)
To determine
The value of the slip speed of the rotor.
(d)
To determine
The value of the rotor frequency in hertz.
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The rotor of a 6-pole, 50-Hz induction motor is rotated by some means at 1000 r.p.m. Compute (i) rotor voltage (ii) rotor frequency (iii) rotor slip and (iv) torque developed. Can the rotor rotate at this speed by itself?
A 3-phase, 4-pole, 230-V, wound rotor induction motor has both its stator and rotor connected in Y. The stator has half as many turns per phase as the rotor. It has a rotor resistance and blocked rotor reactance of 0.09 and 0.385 ohm respectively. If the rotor is turning at 1760 rpm, determine the rotor power developed in hp. *
This question refers to a three-phase induction motor. which statement are false
(A) The slip speed is the synchronous speed minus the rotor speed.
(B) As the rotor speed is loaded, the slip decreases.
(C) The frequency of induced rotor EMF's increases with load on the rotor
(D) The toque on the rotor is due to the interaction of magnetic fields.
Chapter 6 Solutions
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