Transcription of EE320 Homework # 9 Synchronous Machines
1 A a rms EE320 Homework # 9 synchronous machines SOLUTION Problem 1: A 4-pole, 60Hz, Y-connected, 3-phase generator has a regulated terminal line-to-neutral voltage of V as = 260Vr ms 0 , a Synchronous reactance of , a stator resistance of , andLsf = . The balanced 3-phase load draws 2MW at a lagging power f the 3-phase complex power of the load (magnitude and angle) the generator phase current (magnitude and angle; hint: the angle of the current shouldbe negative for the load to have a lagging power f actor) the required excitation voltage ( E ) the required f ield c the required speed of the prime moverProblem 2: Given the same machine as in problem If the excitation voltage is E = 360V 14 and the field current is adjusted to maintain the same terminal voltage as in P roblem , the new generator phase the 3-phase real power c onsumed by the load and identify the new power f the generator efficiency (consider s tator winding losses as the only losses)Problem 3: A 3-phase, Y-connected, 6-pole, 60Hz generator has X S = 1 , negligible rS (statorresistance), and Lsf =.
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