A 80 MVA, 66kV, three-phase, 50 Hz synchronous generator has a synchronous reactance of 10 per...

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A 80 MVA, 66kV, three-phase, 50 Hz synchronous generator has a synchronous reactance of 10 per phase and a negligible resistance. The generator is delivering 90% of rated power at 0.8 power factor lagging at the rated terminal voltage to the grid. Determine the excitation voltage per phase, E, and the power angle, d. i. ii. iii. (8 marks) The generator is now delivering 65 MW at the rated terminal voltage with the excitation voltage of 40 kV per phase. Determine the armature current and the power factor. State whether the power factor is leading or lagging. (7 marks) Based on b(ii), the excitation voltage is decreased to 60% from 40 kV per phase. Find the power angle, armature current, and power factor when the field current is adjusted to the new excitations. A 80 MVA, 66kV, three-phase, 50 Hz synchronous generator has a synchronous reactance of 10 per phase and a negligible resistance. The generator is delivering 90% of rated power at 0.8 power factor lagging at the rated terminal voltage to the grid. Determine the excitation voltage per phase, E, and the power angle, d. i. ii. iii. (8 marks) The generator is now delivering 65 MW at the rated terminal voltage with the excitation voltage of 40 kV per phase. Determine the armature current and the power factor. State whether the power factor is leading or lagging. (7 marks) Based on b(ii), the excitation voltage is decreased to 60% from 40 kV per phase. Find the power angle, armature current, and power factor when the field current is adjusted to the new excitations.