Bundle: Understanding Motor Controls, 4th + Mindtap Electrical, 2 Terms (12 Months) Printed Access Card
4th Edition
ISBN: 9780357097755
Author: Stephen L. Herman
Publisher: Cengage Learning
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Textbook Question
Chapter 43, Problem 1RQ
What are the disadvantages of low-speed, directly coupled induction motors?
Expert Solution & Answer
To determine
The disadvantages of low-speed, directly coupled induction motor.
Explanation of Solution
The directly coupled induction motors are rarely used in the applications where the required speed is below 500rpm. The induction motor take very less current from the supply main.
The vector sum of load current and magnetizing current lags voltage by around 75-80 degrees and hence, the power factor is low. Due to high magnetizing current, the copper losses of the motor increase. This in turn leads to decrease in the efficiency of the motor.
Thus Disadvantage of low-speed, directly coupled induction motors are low power factor and low efficiency.
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Chapter 43 Solutions
Bundle: Understanding Motor Controls, 4th + Mindtap Electrical, 2 Terms (12 Months) Printed Access Card
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