Question

If all the sequence voltages at the fault point in a power system are equal, then the fault is:

• A. Three phase fault
• B. LG fault
• C. LL fault
• D. LLG fault

Hint:

When all sequence voltages are equal, it typically indicates an LLG fault, where the fault affects two lines and the ground.

Answer 1

The Correct Option is D

In a power system, the sequence voltages represent the positive, negative, and zero sequence components of the system. If all the sequence voltages are equal at the fault point, this indicates that the fault is a Line-to-Line-to-Ground (LLG) fault, as this type of fault will affect all three phases equally, resulting in equal sequence voltages. Thus, the correct answer is LLG fault.