permeability: a material property that describes how easily magnetic field flows through the material, analogous to how conductivity describes how easily current flows through a material. permeance: relationship between flux and MMF for a block of material, analogous to electrical conductance. permeance coefficient:
operating point of a permanent magnet in a magnetic circuit.
phase: a motor winding that has a known angular relationship with respect to other phases. phase offset: the number of slots that the coils of one phase winding are shifted relative to those of the next phase. phase windings: a collection of coils connected together to form a phase. pitch: measure of length or angle. pole: a magnetic pole, e.g., a North or South magnetic pole, formed by permanent magnets or energized coils. pole pair: the combination of one North and one South magnetic pole. pole pitch: the period or distance between magnet poles, i.e., the distance from the center of one magnet pole to the center of the next magnet pole having an opposite magnetization direction, can be expressed as a distance or an angular quantity. proximity effect: a phenomenon whereby current crowds towards the outer surface of a conductor due to an externally-applied magnetic field. principle angle: an equivalent angle between -180° and 180°. printed circuit board motor: an axial flux motor where the stator windings are formed and attached to a printed circuit board. rare earth: refers to the permanent magnets materials samarium-cobalt and neodymium-iron-boron, which contain raretearth elements. r
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recoil: the movement of the B-H curve of a material after it has been magnetized. relative permeability: the permeability of a material relative to that of air. relative permeance: a correction factor that modifies the flux density entering the stator in the area of the stator slots.