Answered: Say Which of the following is the main…

Say Which of the following is the main purpose of commutating poles in DC machine ? To stabalise the speed To increase the starting torque To increase the counter emf To eliminate sparking at brushes

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter39: Synchronous Motor Operation

Section: Chapter Questions

Problem 12SQ

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Concept explainers

Winding and Constructions

Alternating Current (AC) winding is generally of the 3-phase type due to the inherent advantages of the 3-phase machine. Armature coils must be connected to the yield balance (equivalent in magnitude and 2/3 of the series phase difference of the rod) 3-phase electromotive forces (emf). The armature should be divided into step-bands to start with slots around the perimeter.In the construction of AC machines, the frame is used as an external protective shield to protect it from environmental conditions. The frame also serves as the outer perimeter, allowing the interior to be easily placed. The static state section of the devices is the stator winding attached stator.

Question

Which of the following is the main purpose of commutating poles in DC machine ?
To stabalise the speed
To increase the starting torque
To increase the counter emf
To eliminate sparking at brushes

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Winding and Construction of the Rotor and Stator

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