A 3-phase, 5 kVA, 208 V, four-pole, 60 Hz, Y-connected synchronous machine has negligible stator winding...

A 3-phase, 5 kVA, 208 V, four-pole, 60 Hz, Y-connected synchronous machine has negligible stator
winding resistance and a synchronous reactance of 8
per phase at rated terminal voltage. Themachine is operated as a generator and delivers rated kVA at 0.8 power factor lagging.

(a) Determine the excitation voltage,
(b) Find the power angle,
(c) Draw the phasor diagram,
(d) Find the stator current assuming that the field excitation current is now increased by 20 %
(without changing the prime mover power).

Expert Solution

samet mamat answered 2 years ago

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