A wound-field DC motor has an armature resistance of 0.50 2 and a mechanical loss torque of 1.0 Nm at full-load speed. The armature voltage is 240 V and the no-load speed of the motor is 2500 rpm. If at full-load the shaft torque is 60.0 Nm and the field flux is reduced by 5% at full-load, determine: (i) The value of Kø,, where K is the armature constant and dis the field flux, at no-load and full-load. (ii) The full-load armature current. (iii) The full-load motor speed. (iv) The full-load efficiency of the motor if the power lost in the field winding is 100 W.

A wound-field DC motor has an armature resistance of 0.50 2 and a mechanical loss torque of 1.0 Nm at full-load speed. The armature voltage is 240 V and the no-load speed of the motor is 2500 rpm. If at full-load the shaft torque is 60.0 Nm and the field flux is reduced by 5% at full-load, determine: (i) The value of Kø,, where K is the armature constant and dis the field flux, at no-load and full-load. (ii) The full-load armature current. (iii) The full-load motor speed. (iv) The full-load efficiency of the motor if the power lost in the field winding is 100 W.

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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