Accuracy-Enhanced Algorithms for the Slot Leakage Inductance Computation of Double-Layer Windings

The paper presents original developments concerning the analytical computation of the slot leakage inductive parameters referring to unsaturated rotating electrical machines. In particular, the double-layer winding layout and arbitrary-shaped semi-closed slots are considered. The conventional analytical formulations of the self-and mutual-inductances of the two layers are initially presented, together with the algorithm developed for their computations. Then, the error causes laying on the simplifying assumptions are discussed and two corrections are applied to the conventional equations to enhance their accuracy with respect to finite element method estimations. Numerical examples of the magnetic energy stored in several slot geometrical domains are included in order to show the potentialities of the proposed analytical approach.