1. In a power system with negligible resistance, the three-phase fault current at a point is...

1. In a power system with negligible resistance, the three-phase fault current at a point is 8 pu. The series reactance to be inserted at the fault point to limit the short circuit current to 5 pu

2. A 3-phase, 15 MVA, 10 kV alternator has internal reactance of 6% and negligible resistance. Find the external reactance per phase to be connected in series with the alternator so that steady current on short circuit does not exceed 6 times the full load current.

3. A 3-phase, 13.8 kV, 50 MVA alternator has positive, negative and zero sequence of 0.20, 0.20 and 0.05 pu. If the alternator is on no-load, determine the fault current for a three-phase fault.

Expert Solution

Manojponduru answered 10 months ago

For a balanced three-phase system, show that the total power is constant. ?

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