On the basis of the known fact that all air gap main flux density variations
are enclosed by permeance slot harmonics, only one component of stray losses
in rotor (stator) iron is considered in the new classification, instead of 2
components: rotor (stator) pulsation iron losses, and rotor (stator) surface
iron losses. No-load rotor cage (high-frequency) stray losses are usually
calculated. No-load stray losses are caused by the existence of space
harmonics: the air-gap slot permeance harmonics and the harmonics produced by
no-load MMF harmonics. The second result is the proof that the corresponding
components of stray losses can be calculated separately for the mentioned
kind of harmonics. Determination of the depth of flux penetration and
calculations of high frequency iron losses are improved. On the basis of
experimental validation, it is proved that the new classification of no-load
stray losses and the proposed method for the calculation of the total value
is sufficiently accurate.
Calculation improvement of no-load stray losses in induction motors with experimental validation
