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…
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…
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…
Construction of Sequence Network in Power System: Before sections the Sequence Network of various Power System elements synchronous machines, transformers and lines have been given. Using these, the Construction of Sequence Network in Power System…
Sequence Impedance and Networks of Transformers: It is well known that almost all present day installations have three-phase transformers since they entail lower initial cost, have smaller space requirements and higher efficiency. The positive sequence…
Zero Sequence Impedance of Transmission Line: Zero Sequence Impedance of Transmission Line - A fully transposed three-phase line is completely symmetrical and therefore the per phase impedance offered by it is independent of the phase…
Sequence Impedances and Networks of Synchronous Machine: Sequence Impedances and Networks of Synchronous Machine - Figure 10.11 depicts an unloaded synchronous machine (generator or motor) grounded through a reactor (impedance Zn). Ea, Eb and Ec are…
Sequence Impedances of Transmission Lines: Sequence Impedances of Transmission Lines - Figure 10.9 shows the circuit of a fully transposed line carrying unbalanced currents. The return path for In is sufficiently away for the mutual…
Phase Shift in Star Delta Transformer: Positive and negative sequence voltages and currents undergo a Phase Shift in Star Delta Transformer which depends upon the labelling of terminals. Before considering this phase shift, we need…
Symmetrical Component Transformation: Symmetrical Component Transformation is given by a set of three balanced voltages (phasors) Va,Vb,Vc is characterized by equal magnitudes and interphase differences of 120°. The set is said to have a phase…
