Q 4/ A 3000 kVA, 3-phase, star-connected, 50 Hz, 2800 V alternator has resistance 0.120. A field current of 60 A produces a short circuit equal to full load current of 618 A in each line. The same field current produces an emf of 800 V on open circuit. Determine : 1_Synchronous Impedance. . 2_Synchronous Reactance.. . 3_Phase Current.. .Amp 4_The excitation voltage of the machine ...V. at 0.8 power factor lagging * 5_The full load regulation at 0.8 power factor lagging. e 9:12 älues

Q 4/ A 3000 kVA, 3-phase, star-connected, 50 Hz, 2800 V alternator has resistance 0.120. A field current of 60 A produces a short circuit equal to full load current of 618 A in each line. The same field current produces an emf of 800 V on open circuit. Determine : 1_Synchronous Impedance. . 2_Synchronous Reactance.. . 3_Phase Current.. .Amp 4_The excitation voltage of the machine ...V. at 0.8 power factor lagging * 5_The full load regulation at 0.8 power factor lagging. e 9:12 älues

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 2.41P

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Consider a three-phase generator rated 300MVA,23kV, supplying a system load of 240 MA and 0.9 power factor lagging at 230 kV through a 330MVA,23/230Y-kV step-up transformer with a leakage reactance of 0.11 per unit. (a) Neglecting the exciting current and choosing base values at the load of 100 MVL and 230 kV. Find the phasor currents IA,IB, and IC supplied to the load in per unit. (b) By choosing the load terminal voltage IA as reference, specify the proper base for the generator circuit and determine the generator voltage V as well as the phasor currents IA,IB, and IC, from the generator. (Note: Take into account the phase shift of the transformer.) (C) Find the generator terminal voltage in kV and the real power supplied by the generator in MW. (d) By omitting the transformer phase shift altogether, check to see whether you get the same magnitude of generator terminal voltage and real power delivered by the generator.
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