8-) A 15-hp, 220-V series DC motor has an armature resistance of 0.120 and a series fieldresistance of 0.07 N. At full load, the input current is 60 A, and the rated speed is 1100rpm. The motor magnetization curve is shown in the figure below. The core losses are 430w, and mechanical losses are 465 W at full load. Suppose the mechanical losses vary asthe speed of the motor, by the fractional power of 2.5, i.e., (speed)25.a) What is the efficiency of the motor at full load?b) What is the speed and torque of the motor if it is operating at 45 A armaturecurrent? 160150140Speed - 1200 tmin13012011010090807060S04030201010Series field current, AFigure 2. The magnetization curve for the series motor in question 8,at a constant speed of 1200 r/min.Internal generated voltage E, V

Part (a) Output power of given motor is, Po=15×746Po=11190 W Input power is,…

8-) A 15-hp, 220-V series DC motor has an armature resistance of 0.120 and a series field resistance of 0.07 N. At full load, the input current is 60 A, and the rated speed is 1100 rpm. The motor magnetization curve is shown in the figure below. The core losses are 430 w, and mechanical losses are 465 W at full load. Suppose the mechanical losses vary as the speed of the motor, by the fractional power of 2.5, i.e., (speed)²5. a) What is the efficiency of the motor at full load? b) What is the speed and torque of the motor if it is operating at 45 A armature current?

8-) A 15-hp, 220-V series DC motor has an armature resistance of 0.120 and a series field resistance of 0.07 N. At full load, the input current is 60 A, and the rated speed is 1100 rpm. The motor magnetization curve is shown in the figure below. The core losses are 430 w, and mechanical losses are 465 W at full load. Suppose the mechanical losses vary as the speed of the motor, by the fractional power of 2.5, i.e., (speed)²5. a) What is the efficiency of the motor at full load? b) What is the speed and torque of the motor if it is operating at 45 A armature current?

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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