Saturated permeance of identically, doubly-slotted magnetic structures

The saturated permeance of the teeth-airgap region in doubly-slotted magnetic structures is expressed as a product of the unsaturated one and its associated permeance saturation factor, each of which depends on only three independent variables. The normalised overlapping width of opposite teeth is introduced as a new independent variable, which makes the reduction of the number of governing parameters describing the saturation permeance variations possible and greatly relieves the permeance data storage requirement. It was found that the permeance saturation factor is strongly dependent on the normalised MMF and overlapping width of opposite teeth, but weakly depends on the ratio of tooth width and pitch. The new saturated permeance database presented is used to predict the torque/displacement curve of a variable reluctance stepping motor, and the predicted one is found to be in good agreement with measured values