HW4/A train is driven by a DC machine with independent electrical excitation. At a speed of 1500 rpm, the following magnetization characteristic has been measured. 390 720 4 8 1- Sketch the equivalent circuit of the DC machine. 2- Why is a voltage induced in the armature when the excitation current is Ea(V) 30 If(A) 0 850 10 1080 1100 1110 28.8 12.8 14.4 zero? 3- Why does the induced voltage at high excitation currents not increase proportional to the excitation current?

HW4/A train is driven by a DC machine with independent electrical excitation. At a speed of 1500 rpm, the following magnetization characteristic has been measured. 390 720 4 8 1- Sketch the equivalent circuit of the DC machine. 2- Why is a voltage induced in the armature when the excitation current is Ea(V) 30 If(A) 0 850 10 1080 1100 1110 28.8 12.8 14.4 zero? 3- Why does the induced voltage at high excitation currents not increase proportional to the excitation current?

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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