| Abstract |
In the application of inverter-fed ac-machines, the lamination material used shows - despite of all
assumptions - not too little material anisotropy effects. Since the sheets have a sufficiently small
thickness and are manufactured by a rolling and punching process, they meet all physical requirements
to show anisotropic distribution of the crystalline energy. The effect is smaller than known for the
grain-oriented steels applied in transformers, however is still observable, as measurements on
lamination material specimen will show. Lamination material anisotropy has mostly been neglected up
to now, because the fundamental wave behaviour of induction machines is only negligible influenced.
Although this effect is only visible in the transient electrical behaviour, in some cases it has to be
considered to ensure proper function and high dynamics of sensorless controlled ac-drives.
However, not only mechanical sensorless control but also condition monitoring schemes for acmachines
evaluate this transient electrical behaviour and thus the lamination material anisotropy
effects are of great importance in these fields. |
