Question

The first step in power-system fault calculations is to develop sequence networks based on the single-line diagram of the system, and then reduce them to their Thévenin equivalents, as viewed from the fault location.

(a) True (b) False

Short answer

The correct answer is (a) True.

Step-by-step solution

Definition of power-system fault calculation.

A power system fault calculation is a method by which system makes equal impedance and equal quantities over different voltages level to a common base. By eliminating the impact of varying voltages level, due to important calculations are clarify.

Determine for power-system fault studies.

In a power system fault analysis, the power system runs under normal steady-state conditions at prefault condition. Thus, the sequence networks are always disconnected as soon as the fault occurs. While at the time of the Fault, the sequences are interconnected in case of the fault that is unsymmetrical in nature.

The fault current are zero in a sequence component before a fault occurs. Hence, the sequence networks are reduced in form of Thévenin equivalent circuits and put at fault terminals. Every sequence networks have equal to prefault voltage of Thévenin equivalent impedance and Thévenin equivalent voltage source.

Therefore, the correct answer is (a) True.