A Hanna curve is a curve defining magnetic parameters of an inductor. Alex Goldman, Magnetic Components for Power Electronics

Hanna curves help in finding optimum working conditions (maximum energy stored in an air gap) for an inductor. Several parameters are taken into account, including: magnetic field or flux density level, size of an air gap, physical dimensions of the magnetic core, number of turns of the winding, etc.Example of calculation of Hanna curve

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