Two 3-phase, 7.4 kV, star-connected alternators supply a load of 3008 kW at 0.8 pf lagging. The synchronous impedance per phase of machine 1 is (0.5 + j10) and of machine 2 is (0.4+j18). The excitation of machine 1 is adjusted so that it delivers 150 A at a lagging power factor and the governors are set that load is shared equally between the machines. Determine (a) the current in phasor, (b) power factor (c) the induced emf (line) and (d) the load angle of each machine.

Two 3-phase, 7.4 kV, star-connected alternators supply a load of 3008 kW at 0.8 pf lagging. The synchronous impedance per phase of machine 1 is (0.5 + j10) and of machine 2 is (0.4+j18). The excitation of machine 1 is adjusted so that it delivers 150 A at a lagging power factor and the governors are set that load is shared equally between the machines. Determine (a) the current in phasor, (b) power factor (c) the induced emf (line) and (d) the load angle of each machine.

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

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.11P

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