22.5.2014 Soft magnetic composites

Modelling and experimental analysis of core losses of SMC components

The development of high speed electrical machines and the use of harmonic rich controls demand magnetic cores of good high frequency performance. Soft Magnetic Composite (SMC) can be a suitable alternative material for such applications because of its low eddy current loss. On the other hand, there is a variety of SMC materials with different magnetic properties such as, permeability, resistivity, and coercivity due to particle size variation, in addition, various insolation coating technologies may be utilized. Furthermore, the performance of a SMC core can be tailored by manufacturing processes such as compaction pressure, heat treatment temperature and atmosphere, etc.

In this work the hysteresis loss, particle eddy current loss and component bulk eddy current loss of SMC magnetic cores are analysed with the aim to facilitate the selection of suitable materials and manufacturing processes for different applications. A core loss model is proposed to estimate core losses in SMC cores for currents of sinus waveform. The parameters required for core loss calculation of several Somaloy® materials are extracted from measured core losses of standard magnet rings. Finally, an attempt to position different Somaloy® for different applications is made.