A dc series motor has an armatureresistance of 0.06 Q and series fieldresistance of 0.08 Q. The motor isconnected to a 400 V supply. The linecurrent is 20 A when the speed of themachine is 1100 rpm. When the line currentis 50 A and the excitation is increased to30%, the speed of the machine in rpm is837 RPM938 RPM1003 RPMO 1100 RPMA d.c. series motor takes 40 A at 220 V andruns at 800 r.p.m. If the armature and fieldresistance are 0.2 Q and 0.1 Q respectivelyand the iron and friction losses are 0.5 kW,the torque developed in the armature andthe output of the motor will be80.5 N-m , 11.57 kW96.2 N-m, 10.63 kW99.3 N-m, 7.82 kW

As two questions are different so iam solving only one question i.e 1st question. take ratio of back…

A dc series motor has an armature resistance of 0.06 Q and series field resistance of 0.08 Q. The motor is connected to a 400 V supply. The line current is 20 A when the speed of the machine is 1100 rpm. When the line current is 50 A and the excitation is increased to 30%, the speed of the machine in rpm is O 837 RPM O 938 RPM O 1003 RPM O 1100 RPM

A dc series motor has an armature resistance of 0.06 Q and series field resistance of 0.08 Q. The motor is connected to a 400 V supply. The line current is 20 A when the speed of the machine is 1100 rpm. When the line current is 50 A and the excitation is increased to 30%, the speed of the machine in rpm is O 837 RPM O 938 RPM O 1003 RPM O 1100 RPM

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter37: Automatic Speed Control For Wound Rotor Motors

Section: Chapter Questions

Problem 1SQ

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