5. A d.c. shunt machine has armature and field resistances of 0.025 Ω and 80 Ω respectively. When connected to constant 400-V bus-bars and driven as a generator at 450 r.p.m., it delivers 120 kW. (a) Calculate its speed when running as a motor and absorbing 120 kW from the same bus-bars. (b) Deduce the direction of rotation of this machine when it is working as a motor assuming a clockwise rotation as a generator

5. A d.c. shunt machine has armature and field resistances of 0.025 Ω and 80 Ω respectively. When connected to constant 400-V bus-bars and driven as a generator at 450 r.p.m., it delivers 120 kW. (a) Calculate its speed when running as a motor and absorbing 120 kW from the same bus-bars. (b) Deduce the direction of rotation of this machine when it is working as a motor assuming a clockwise rotation as a generator

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 6.45P

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