Reconsider the synchronous generator of Problem 8.36. Obtain sequencenetwork representations for the following fault conditions.

(a) A short-circuit between phases \(b\) and \(c\).

(b) A double line-to-ground fault with phases \(b\) and \(c\) grounded.

Problem 8.36

Consider Figures 8.13 and 8.14 of the text with reference to a Y-connected synchronous generator (grounded through a neutral impedance \(Z_{n}\) ) operating at no load. For a line-to-ground fault occurring on phase \(a\) of the generator, list the constraints on the currents and voltages in the phase domain, transform those into the sequence domain, and then obtain a sequence-network representation. Also, find the expression for the fault current in phase \(a\).

Figure 8.13

Figure 8.14

Transcribed Image Text:

20 MVA 0.1 per unit G FX 40 MVA 0.15 per unit G X 20 MVA 0.05 per unit X 40 MVA 0.15 per unit G3 16 MVA 0.04 per unit