Q1 (a) the following figures refer to the magnetization curve of a d.c. series motor running onno load circuit at 640 r.p.m. The total resistance of the machine is 0.78 ohm. Plot thespeed/torque curve of the motor when operating on a 550-V supplyCurrent (A)Generated e.m.f. (V)20406080100215380485550590Q2 (a) Two d.c. shunt generators Gl and G2,with ratingsrespectively, and having the voltage vs. percent current external characteristics shown660아650640630-곧 62아610 VeLGenerator Aof 500and750 kW,Generator Bin figure below are connected in parallel.Calculate (i) the power output of each 590-generator and the total load when the 580-terminal voltage is 630 volts; (ii) the loaddelivered by generator G1 when generatorG2 is "floating"1010201004050Per cent of rated current3060708090(34)Q3 (a) Rheostatic braking is used to limit the speed of a d.c. crane motor to 600 r.p.m. whenthe supply is cut off. The motor has a resistance of 1 ohm and the descending load exerts atorque o 200 N.m. calculate the approximate value of the resistance to be connected acrossthe motor terminals. Points on the magnetization curve at 600 r.p.m. are:Current (A) 42e.m.f. (V)434445383390397403

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Q1 (a) the following figures refer to the magnetization curve of a d.c. series motor running on no load circuit at 640 r.p.m. The total resistance of the machine is 0.78 ohm. Plot the speed/torque curve of the motor when operating on a 550-V supply Current (A) Generated e.m.f. (V) 215 20 40 60 80 100 380 485 550 590

Q1 (a) the following figures refer to the magnetization curve of a d.c. series motor running on no load circuit at 640 r.p.m. The total resistance of the machine is 0.78 ohm. Plot the speed/torque curve of the motor when operating on a 550-V supply Current (A) Generated e.m.f. (V) 215 20 40 60 80 100 380 485 550 590

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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