The nameplate of a separately excited de motor reads 18.5 kW, 230 V armature, 1200 rpm. The field current is kept constant. Field losses are equal to 900 W. The arma- ture resistance is 0.185 N. Under the rated condition, the motor draws 93 A. A constant mechanical loss 1145 W is assumed. The motor is supplied from a power converter with adjustable voltage and capable of absorbing power. Find, for a speed of 800 rpm and an applied voltage of 125 V: (a) The armature current. Indicate the mode of operation of the machine, motoring or generating. (b) The shaft torque. (c) The machine efficiency.

The nameplate of a separately excited de motor reads 18.5 kW, 230 V armature, 1200 rpm. The field current is kept constant. Field losses are equal to 900 W. The arma- ture resistance is 0.185 N. Under the rated condition, the motor draws 93 A. A constant mechanical loss 1145 W is assumed. The motor is supplied from a power converter with adjustable voltage and capable of absorbing power. Find, for a speed of 800 rpm and an applied voltage of 125 V: (a) The armature current. Indicate the mode of operation of the machine, motoring or generating. (b) The shaft torque. (c) The machine efficiency.

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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