Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Question
Chapter 51, Problem 1SQ
To determine
Explain why the three phase braking reduces motor heating when compared with single phase breaking.
Expert Solution & Answer
Explanation of Solution
Discussion:
A DC dynamic brake is a single phase braking used in various induction motors. It requires more current to achieve the braking torque. Therefore, the heat dissipation is more in single phase braking. In a three phase braking, the motor requires less current for the same braking torque, so that the motor heating reduces. Due to the additional winding in a three phase braking motors, the ampere turns are gained.
Conclusion:
Thus, the reason for the reduction of motor heat in three phase braking is explained.
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Chapter 51 Solutions
Electric Motor Control
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