Question 2. (5 points) A variable speed DC shunt machine has a rated speed of 2000 rpm and itis connected to a mechanical load that requires a constant-torque of 200 Nm. At the rated speed,the armature circuit draws 100 A. The DC supply voltage is 450 V.(b) The speed of the machine is now reduced to 1500 rpm with armature resistance control andthe flux remains constant. Determine the required rheostat in the armature circuit to achievethe new speed.(c) Determine the efficiency of the machine for the condition in (b).(d) Sketch a plot that shows the relationship between the speed and the torque. Highlight therange of the required rheostat to vary the speed from 2000 rpm to 1500 rpm.

Given Data:1. Rated speed, n1=2000rpm 2. New speed, n2=1500rpm3. Torque, T = 200 Nm (constant)4.…

Answered: Question 2. (5 points) A variable speed…

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter5: Resistors

Section: Chapter Questions

Problem 1PA

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