A 3-phase, 5 kVA, 208 V, 4-pole, 60 Hz, star-connected synchronous generator has negligible stator winding...

A 3-phase, 5 kVA, 208 V, 4-pole, 60 Hz, star-connected synchronous generator has negligible stator winding resistance and a synchronous reactance of 8 Ω per phase at the rated terminal voltage. The generator is connected in parallel to a 3-phase, 208 V, 60 Hz infinite bus. All losses may be neglected.

a) Determine the excitation voltage and the power angle when the machine is delivering rated apparent power at 0.8 PF lagging.

b) If the field excitation is increased by 20 % without changing the prime mover power, find the stator current, power factor, and reactive power supplied by the machine.

c) With the field current as in (a), determine the maximum power with which the generator can be supplied without losing synchronism? What are the corresponding stator current and power factor at this maximum power condition?

Expert Solution

Manojponduru answered 1 year ago

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