Understanding Motor Controls
4th Edition
ISBN: 9781337798686
Author: Stephen L. Herman
Publisher: Delmar Cengage Learning
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Question
Chapter 35, Problem 1RQ
To determine
The electronic component generally used to change AC to DC voltage in large DC motor controllers.
Expert Solution & Answer

Explanation of Solution
The alternating current (AC) voltage is converted to direct current (DC) voltage in DC motors using two separate power supplies. By using two separate power supplies instead of resistors connected in series to the armature, it is smoother to control the speed of the DC motor.
One of the supplies is constant and connected to the shunt field and the other is a variable power supply connected to the armature.
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Chapter 35 Solutions
Understanding Motor Controls
Ch. 35 - Prob. 1RQCh. 35 - Why is this component used instead of a diode?Ch. 35 - What is a freewheeling or kickback diode?Ch. 35 - Name two methods of sensing the current flow...Ch. 35 - Prob. 5RQCh. 35 - What unit controls the voltage applied to the...Ch. 35 - What device is often used to sense motor speed?
Ch. 35 - Prob. 8RQ
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