A three-phase, 6-pole, 60 Hz, wye-connected synchronous machine has X = 20 and negligible stator resistance. Assume the
Posted: Fri May 20, 2022 10:04 pm
A three-phase, 6-pole, 60 Hz, wye-connected synchronous machine has X = 20 and negligible stator resistance. Assume the machine is connected to the grid and operated as a generator with a terminal voltage of 230 V (mms, line-to-line) delivering 20,000 Watts (3-phase) and 12,000 Vars (3-phase). Assume the phase angle on the per-phase terminal voltage is zero. a) What is the synchronous mechanical speed of the generator in RPM? Speed- b) Calculate the magnitude of the per-phase excitation voltage E, in volts and the torque angle in degrees. Ear- 6= c) Assume that a rotor field current of 10 A sets the per-phase excitation voltage as Ex=100v. If the real power produced by the generator is to remain the same at 20,000 Watts (3-phase), what value of field current is needed to change the power factor of the power it is producing to one? Rotor field current