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Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

high phase order (HPO)
polyphase systems that contain 6, 9, or more phases ather than the standard three-phase system.

HPO systems may be used to provide a means of transmitting more electrical power down existing right-of-ways than three-phase systems, without an increase in transmission voltage, and without an increase in EMF levels at the edge of the right-of-way.