30. A series motor runs at 900 rev/min when taking 30 A at 230 V. The 2 total resistance of the armature and field circuits is 0-8 2. Calculate the values of the additional resistance required in series with the machine to reduce the speed to 500 rev/min if the gross torque is: (a) constant; (b) proportional to the speed; (c) proportional to the square of the speed. Assume the magnetic circuit to be unsaturated.

30. A series motor runs at 900 rev/min when taking 30 A at 230 V. The 2 total resistance of the armature and field circuits is 0-8 2. Calculate the values of the additional resistance required in series with the machine to reduce the speed to 500 rev/min if the gross torque is: (a) constant; (b) proportional to the speed; (c) proportional to the square of the speed. Assume the magnetic circuit to be unsaturated.

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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Concept explainers

Stator and Rotor Magnetic Field

The stator and rotor magnetic field is the resulting magnetic field generated by a system of coils that are symmetrically aligned. They are supplied with polyphase currents. The magnetic field is generated by poly-phase (two or more phases) current or single-phase current. In the latter case, two field stator windings are supplied and two resulting electromagnetic fields are generated beyond the stage.

Question

Os2 total resistance of the armature and field circuits is 0-8 2. Calculate
30. A series motor runs at 900 rev/nmin when taking 30 A at 230 V. The
the values of the additional resistance required in series with the
machine to reduce the speed to 500 rev/min if the gross torque is: (a)
constant; (b) proportional to the speed; (c) proportional to the square
of the speed. Assume the magnetic circuit to be unsaturated..

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