
2-1
2.1 Introduction
Along the airgap of AC rotating electric machines, there are several distributed windings. ese windings
are positioned in the stator and/or rotor magnetic structure (typically inside slots), and they have to pro-
duce suitable magnetomotive force (mmf) waveforms in the airgap. e windings are usually distributed
over a more or less wide airgap circumference arc. ere are a wide range of AC windings, and it is not pos-
sible to provide a complete description of any winding type [1–8]. For this reason, the attention is focused
on symmetrical windings, with particular reference to three-phase windings (induction and synchr