In the last post we examined and calculated the symmetrical components in a non-faulted, three-phase electrical power system. This post expands on the same process of using phasor diagrams to describe, illustrate, visualize and calculate the three symmetrical components: Positive Sequence, Negative Sequence and Zero Sequence. An examination of a phase to neutral (also referred to as phase to ground) fault will be conducted.
Thus, there is significant positive sequence in the phase to neutral fault and the positive sequence phasor is lagging the reference phase (phase A).
Thus, there is some negative sequence in the phase to neutral fault and the negative sequence phasor is leading the reference phase (phase A).
Thus, there is some zero sequence in the phase to neutral fault.