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Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

leakage
the flux in a magnetic circuit that does not do any useful work.
leakage flux
the flux that does not link all the turns of a winding or in coupled circuits, flux that links one winding but not another. For example, the magnetic flux produced by the primary winding of a transformer that is not coupled to the secondary winding.
leakage reactance
the amount of inductive reactance associated with leakage flux. The leakage flux is the flux which traverses in paths farther from the designated paths such as the magnetic core in transformers and the air gap in electric machines and constitutes the non-useful flux. The electric circuit symbol of leakage reactance is Xl . It is a function of the leakage inductance and the frequency of operation. Higher values of leakage reactance affect the regulation and efficiency of the system. Xl is expressed in ohms.
magnetic leakage

See leakage