The following table gives open-circuit voltages fer dierent values of field current for a d.e. generator: Open-circuit voltage (V) Field current (A) 120 240 334 400 444 470 05 1-0 15 2:0 2-5 3-0 Express these values graphically and determine therefrom the generated e.m.f. when the shunt field circuit has a resistance of 200 0 Find also the critical resistance of the shunt field circuit. The effects of armature resistance and brush volt drop may be neglected. (E.M.E.U., 0.1) 6. The following table gives open-circuit voltages fer different values offield current for a d.c. generator:Open-circuit voltage (V)Field current (A)120 240 334 400 444 47005 1-0 15 2:0 2-5 3-0Express these values graphically and determine therefrom thegenerated e.m.f. when the shunt field circuit has a resistance of 200 0Find also the critical resistance of the shunt field circuit. The effectsof armature resistance and brush volt drop may be neglected.(E.M.E.U., 0.1)

Answered: Image /qna-images/answer/e41e60d6-8e23-41bd-a416-589ec51513a5.jpg

6. The following table gives open-circuit voltages fer different values of field current for a d.c. generator: Open-circuit voltage (V) Field current (A) 120 240 334 400 444 470 05 1-0 15 20 2-5 3-0 Express these values graphically and determine therefrom the generated e.m.f. when the shunt field circuit has a resistance of 200 0 Find also the critical resistance of the shunt field circuit. The effects of armature resistance and brush volt drop may be neglected.

6. The following table gives open-circuit voltages fer different values of field current for a d.c. generator: Open-circuit voltage (V) Field current (A) 120 240 334 400 444 470 05 1-0 15 20 2-5 3-0 Express these values graphically and determine therefrom the generated e.m.f. when the shunt field circuit has a resistance of 200 0 Find also the critical resistance of the shunt field circuit. The effects of armature resistance and brush volt drop may be neglected.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.53P

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