What conditions must be fulfilled for the self-excitation of a d.c. shunt generator? The open-circuit characteristic of a shunt-excited d.c. machine, run at 1200 rev/min, is: Terminal voltage (V) Field current (A) 47 85 103 114 122 127 135 141 0-2 0:4 0-6 0:8 1-0 1-2 1-6 2:0 The field coil resistance is 55 Q. Determine: (i) the value of the field-regulating resistance to enable the machine to generate 120 V on open circuit when run at 1200 rev/min; (ii) the value of the open-circuit voltage when the regulator is set to 20 2 and the speed is reduced to 800 rev/min.

What conditions must be fulfilled for the self-excitation of a d.c. shunt generator? The open-circuit characteristic of a shunt-excited d.c. machine, run at 1200 rev/min, is: Terminal voltage (V) Field current (A) 47 85 103 114 122 127 135 141 0-2 0:4 0-6 0:8 1-0 1-2 1-6 2:0 The field coil resistance is 55 Q. Determine: (i) the value of the field-regulating resistance to enable the machine to generate 120 V on open circuit when run at 1200 rev/min; (ii) the value of the open-circuit voltage when the regulator is set to 20 2 and the speed is reduced to 800 rev/min.

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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