1. In a power system with negligible resistance, the three-phasefault current at a point is 8 pu. The series reactance to beinserted at the fault point to limit the short circuit current to 5pu
2. A 3-phase, 15 MVA, 10 kV alternator has internal reactance of6% and negligible resistance. Find the external reactance per phaseto be connected in series with the alternator so that steadycurrent on short circuit does not exceed 6 times the full loadcurrent.
3. A 3-phase, 13.8 kV, 50 MVA alternator has positive, negativeand zero sequence of 0.20, 0.20 and 0.05 pu. If the alternator ison no-load, determine the fault current for a three-phasefault.
