Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Question
Chapter 39, Problem 1SQ
To determine
Explain the reason why both rotor and stator should possess equal number of poles.
Expert Solution & Answer
Answer to Problem 1SQ
The reason why both rotor and stator should possess equal number of poles is to synchronize with each other.
Explanation of Solution
An independent field is established around the rotor, which is energized by a direct current through slip rings mounted on the shaft. The rotor has the same number of coils as the stator, so that each and every rotor pole (north and south) can have an alternative stator poles (north and south), and synchronize with each other. Therefore, the motor’s stator and rotor are in relative speed due to magnetism.
Conclusion:
Thus, the reason why both rotor and stator should possess equal number of poles is to synchronize each other.
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Chapter 39 Solutions
Electric Motor Control
Ch. 39 - Prob. 1SQCh. 39 - What is the effect of the starting winding of the...Ch. 39 - What are typical applications of synchronous...Ch. 39 - Prob. 4SQCh. 39 - A loaded synchronous motor cannot operate...Ch. 39 - Why must a discharge resistor be connected in the...Ch. 39 - Depending on their power factor ratings, what is...Ch. 39 - At what power factor do incandescent lights...Ch. 39 - Prob. 9SQCh. 39 - The speed of a synchronous motor is fixed by the...
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