A four-pole Y-connected three-phase synchronous generator rated at 200-kVA, 415-V, 50-Hz and 0.80-laggining power factor. Its synchronous resistance is 0.0502/phase. Under the full-load conditions, the core losses of this generator are 8 kW, and the friction and windage losses are 10 kW. The generator was tested to determine its equivalent circuit parameters by performing the open- circuit and short-circuit test and the following results were obtained. Open-circuit test Field current, A 0 1 2 3 4 5 6 7 8 9 10 Terminal voltage, V 6.4 175 350 503 638 761 850 935 993 1032 1058 Short-circuit test Field current, A 0 1 2 3 4 5 6 7 8 9 10 141 284 425 567 710 843 981 1122 1264 1393 Armature current, A 5.16 1. Plot and discuss the Open-circuit characteristic (OCC) and short- circuit characteristic (SCC) of this synchronous generator. 2. What is the speed of rotation of this generator? 3. What is the rated current of this generator and its phase angle? 4. What is the saturated synchronous reactance of this generator at the rated conditions? 5. Plot the saturated synchronous reactance of this generator as a function of field current. Confirm the synchronous reactance calculated in (4) using the Xs vs If graph? 6. What is the internal generated voltage and load angle of the generator at rated conditions? Draw the phasor-diagram of the generator representing this operating condition and comment on it. 7. What field current does the generator require to be operating at the rated conditions. 8. What is the voltage regulation of the generator at the rated conditions? 9. If this generator was operating at the rated conditions and the load was suddenly disconnected from the line, what would happen to its terminal voltage? 10. What is the mechanical power supplied to the generator by the prime mover at rated conditions?