What is zero sequence impedance? Is the impedance that equipment or electrical network sees if energized with a single-phase power source in each phase.
Were does it come from? C.L. Fortescue first introduced it in 1918 while working for Westinghouse to resolve unbalanced phasors of a three-phase system using the symmetrical component method.
This method decomposes a three-phase system into three distinct sets of symmetrical components: a positive sequence component, a negative sequence component, and a zero sequence component.
As you see, the sequence components (including the zero sequence) is a mathematical tool used to simplify the solution of unbalance system problems.
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