Types of Unsymmetrical faults in Power System: There are two types of unsymmetrical faults in power system namely, Shunt Type Fault: Single Line to Ground Fault (LG) Line to Line Fault (LL) Double Line to Ground Fault (LLG) Series Type Fault: (i) Open conductor (one or two conductors … (Read More)

Symmetrical Component Analysis of Unsymmetrical Faults: Symmetrical Component Analysis of Unsymmetrical Faults – Consider a general power network shown in Fig. 11.1. It is assumed that a shunt type fault occurs at point F in the system, as a result of … (Read More)

Single Line to Ground Fault: Figure 11.4 shows a Single Line to Ground Fault at F in a power system through a fault impedance Zf. The phases are so labelled that the fault occurs on phase a. At the fault point F, … (Read More)

Line to Line Fault (LL): Figure 11.7 shows a Line to Line Fault at F in a power system on phases b and c through a fault impedance Zf. The phases can always be relabelled, such that the fault is on phases … (Read More)

Double Line to Ground Fault (LLG): Figure 11.9 shows a Double Line to Ground Fault at F in a power system. The fault may in general have an impedance Zf as shown. The current and voltage (to ground) conditions at the fault … (Read More)

Open Conductor Faults: An open conductor faults is in series with the line. Line currents and series voltages between broken ends of the conductors are required to be determined. Figure 11.19 shows currents and voltages in an open conductor faults. The ends … (Read More)

Bus Impedance Matrix Method for Analysis of Unsymmetrical Shunt Faults: Bus Impedance Matrix Method of fault analysis, given for symmetrical faults  can be easily extended to the case of unsymmetrical faults. Consider for example an LG fault on the rth bus … (Read More)