
2-26 Power Electronics and Motor Drives
2.3.6 Harmonic Rotating Fields
In the rotating magnetic eld theory previously analyzed, only the fundamental distributions of mmf
and of ux density have been considered. In fact, in rotating AC electric machines, the “useful” energy
electromechanical conversion depends, almost exclusively, on these fundamental distributions.
In the actual case, together with the fundamental eld distribution, there are a lot of spatial eld har-
monics, as shown in (2.13). e main eect of these harmonics is the distortion of the ideal rotating-eld
wave, adding at the sinusoidal wave other waves rotating a dierent spe ...