Estimation of shallow slot effect on the permeance of doubly-salient structures [stepping and switched reluctance motors]

Two sample calculations for finite slot depth performed using the assumed flux paths method have been carried out and it has been found that the estimated correction factors are overestimated for d/s above 0.5 and underestimated for d/s below 0.4 (in comparison with the finite element computation). The maximum and minimum difference between the two calculated values are 3.6% and 1%, respectively. Considering the approximate nature of the assumed flux paths method the combined procedure used for this calculation shows good agreement with finite element computation and the result can be used at least for handy reference