Symmetrical Fault Analysis Interview Questions and Answers:

1. What is meant by fault level ?

Ans. When fault occurs at a point in a power system, the corresponding MVA is referred to as the fault level at that point.

2. What are current limiting reactors ?

Ans. Current limiting reactors are inductive coils having large inductive reactances in comparison to their resistances and are commonly installed on large power systems to limit the magnitude of short-circuit currents and reduce the resulting voltage disturbances on the rest of the system.

3. Why it is not necessary to insert current limiting reactor between the generator and the generator bus ?

Ans. Since modern generators have sufficient inherent transient reactance to protect themselves against dead 3-phase short circuit at their terminals, insertion of current limiting reactors between the generators and their bus is not necessary.