A 4-pole, lap-wound DC motor, having 420 conductors, rotates in a field of 20 mWb. a. If the motor speed is 1250 rpm, calculate the induced armature voltage. b. Assume that the motor is shunt connected with Ra = 0.5 Ohm and Rf = 240 Ohm. If the motor is started with a full voltage of 180 Vdc, calculate the starting current and the steady state current. Calculate the required starting resistor to limit the starting current to five-time steady state current. c. For the calculated steady state current in part (b), calculate the torque developed by the armature. d. Assume five values of armature current between zero and the maximum steady state current, calculate the speed and torque for each value. Then plot torque vs speed characteristic of the motor based on these five value results.

A 4-pole, lap-wound DC motor, having 420 conductors, rotates in a field of 20 mWb. a. If the motor speed is 1250 rpm, calculate the induced armature voltage. b. Assume that the motor is shunt connected with Ra = 0.5 Ohm and Rf = 240 Ohm. If the motor is started with a full voltage of 180 Vdc, calculate the starting current and the steady state current. Calculate the required starting resistor to limit the starting current to five-time steady state current. c. For the calculated steady state current in part (b), calculate the torque developed by the armature. d. Assume five values of armature current between zero and the maximum steady state current, calculate the speed and torque for each value. Then plot torque vs speed characteristic of the motor based on these five value results.

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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