A 20 kW, 440-V, short-shunt, compound d.c. generator has a full-loade fficiency of 87%. If the resistance of the armature and interpoles is 0.4Ω and that of the series and shunt fields 0.25 Ω and 240 Ω respectively, calculate the combined bearing friction, windage and core-loss of the machine. [Ans. 725 W]

A 20 kW, 440-V, short-shunt, compound d.c. generator has a full-loade fficiency of 87%. If the resistance of the armature and interpoles is 0.4Ω and that of the series and shunt fields 0.25 Ω and 240 Ω respectively, calculate the combined bearing friction, windage and core-loss of the machine. [Ans. 725 W]

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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