A 3-4, 440V, 11KVA, Y-connected cylindrical rotor alternator with synchronous reactance 8/phase is driven by 240V, 11KW DC shunt motor. The alternator is synchronous with infinite bus 440V, 50HZ. All losses are to be ignored (a) Determine excitation EMF & load angle of the alternator when it delivers rated kVA at unity pf (b) With driving torque to DC shunt motor unaltered, the excitation voltage is increased by 20% fid new load angle, current & pf. Also obtain maximum stable power output & corresponding current & pf

A 3-4, 440V, 11KVA, Y-connected cylindrical rotor alternator with synchronous reactance 8/phase is driven by 240V, 11KW DC shunt motor. The alternator is synchronous with infinite bus 440V, 50HZ. All losses are to be ignored (a) Determine excitation EMF & load angle of the alternator when it delivers rated kVA at unity pf (b) With driving torque to DC shunt motor unaltered, the excitation voltage is increased by 20% fid new load angle, current & pf. Also obtain maximum stable power output & corresponding current & pf

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 11.8P

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