A 220 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 ohm. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is

A 220 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 ohm. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter8: Basic Electric Motors

Section: Chapter Questions

Problem 2RQ

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Concept explainers

DC Generator

An electromechanical machine which converts input mechanical energy to respective output electric energy is called a generator.

Question

Machine problem

A 220 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 ohm. If the
machine is now operated as a motor at same terminal voltage and current but with the flux increased by
10%, the ratio of motor speed to generator speed is

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