Sketch the load characteristic of a d.c. generator with (i) shunt (ii) series excitation. Give reasons for the particular shape in each case. The O.C.C. at 700 r.p.m. of a series generator with separately-excited field is as follows : Field current (A) : 20 40 50 60 75 Armature e.m.f. (V) : 190 360 410 450 480 Determine the current and terminal voltage as a self-excited series machine when running at 600 r.p.m. with a load of 6 Ω connected to the terminal. Resistance of armature and series winding is 0.3Ω. Ignore effect of armature reaction.

Sketch the load characteristic of a d.c. generator with (i) shunt (ii) series excitation. Give reasons for the particular shape in each case. The O.C.C. at 700 r.p.m. of a series generator with separately-excited field is as follows : Field current (A) : 20 40 50 60 75 Armature e.m.f. (V) : 190 360 410 450 480 Determine the current and terminal voltage as a self-excited series machine when running at 600 r.p.m. with a load of 6 Ω connected to the terminal. Resistance of armature and series winding is 0.3Ω. Ignore effect of armature reaction.

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

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.3P

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