Three-phase electric power

Form of alternating current

Three-phase electric power (abbreviated 3ϕ) is the most widely used form of alternating current (AC) for electricity generation, transmission, and distribution. It is a type of polyphase system that uses three wires (or four, if a neutral return is included; not counting any protective conductor) and is the standard method by which electrical grids deliver power around the world. In a three-phase system, each of the three phases is offset by 120 degrees of phase shift relative to the others.

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