- A For Questions 2 A 2 B Demonstrate All Your Calculations In Per Unit And Then Convert To Real Values The Ratings O 1 (67.17 KiB) Viewed 34 times
a) For
questions 2(a)-2(b), demonstrate all your calculations in per-unit and then convert to real values. The ratings of a three-phase round-rotor synchronous generator are given as 415 MVA, 45 kV, 0.84 power factor lagging. The characteristic reactance of the generator is 2.4 2. At rated voltage, if the generator is supplying full load 415 MVA at a 0.84 lagging power factor, determine the rotor angle &, the electromotive force owing to the rotor field (E) (i.e., excitation EMF) of the generator, and the reactive power consumed by the load connected to the generator. [4 Marks] b) When the synchronous generator in
question 2(a) is supplying the full real power load at rated voltage, i) What would be the rotor angle 8, load power factor, and the reactive power consumed by the load if E in 2(a) is increased by 35% ? [3 Marks] ii) What would be the rotor angle 8, load power factor, and the reactive power consumed by the load if E in 2(a) is decreased by 35%? [3 Marks] c) Draw the impacts of different excitation EMFs of the synchronous generator in
questions 2(a), 2(b)-(i) and 2(b)-(ii) on a single phasor diagram. Clearly mark the corresponding rotor angles 8, excitation currents, power factor angles, load voltages, and excitation EMFS. [5 Marks]