A separately excited DC motor presents the following plate data. • armature voltage: V • amature current: I = 30 A = 220 V an an • speed: n = 3000 rpm • excitation voltage: V = 80 V excitation current: I = 4 A starting current: I = 180 A Neglecting the no load losses and the saturation of the magnetic circuit, evaluate: 1) the amature resistance Ra %3D 2) the coefficent between e.m.f. and speed [Vrad/s] 3) the rated torque [Nm] 4) the rated efficiency [%] 5) the speed when the motor delivers 1.5 T (constant flux) n = [rpm]

A separately excited DC motor presents the following plate data. • armature voltage: V • amature current: I = 30 A = 220 V an an • speed: n = 3000 rpm • excitation voltage: V = 80 V excitation current: I = 4 A starting current: I = 180 A Neglecting the no load losses and the saturation of the magnetic circuit, evaluate: 1) the amature resistance Ra %3D 2) the coefficent between e.m.f. and speed [Vrad/s] 3) the rated torque [Nm] 4) the rated efficiency [%] 5) the speed when the motor delivers 1.5 T (constant flux) n = [rpm]

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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