Question

A three-phase, 9,375 kVA, 13.8 kV, 4-pole, 60 Hz, Y-connected synchronous generator has a synchronous reactance, Xs = 17.9, and is connected to an infinite bus at rated voltage. If the rotational and electrical losses are negligivle, what is Ia, Ef, delta, theta, Tdrive, Phasor diagram, and power flow diagram (label completely with numerical values for,

A) the machine as a generator; the prime-throttle is opened and If is adjusted so that the machine delivers rated kVA, 0.8 pf lagging, to the line.

B) the machine floating on the line; the prime-mover throttle is closed and If remains unchanged from part (a).

C) The machine is a generator; the drive torque is adjusted so that maximum power is delivered to the line with If remaining unchanged from part (a).

Answer #1

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