Different novel methods for reduction of low space harmonics for the fractional slot concentrated windings

Two different costs effective and high efficiency methods for improving the main performances of tooth concentrated windings are presented. Using these simple techniques it is possible to reduce or even to cancel some space harmonics of low order resulting in lower magnet and iron losses induced by the armature reaction field. The presented techniques are applied for different 12-teeth/10-poles PM machines and the obtained results show enormous improvements on the machine performances.