Abstract:
Since electric motors were invented, efforts to increase their power density have been continuously spent. Motor mass, raw material cost, floor space, user flexibility et al. could all be positively influenced by this trend, being itself enabled by both steady and quantum advancements in many technological disciplines. Loads requiring higher than usual speeds for optimal operation, are ever less driven by traditional motor-gearbox combinations. High speed motors are claiming their place today. Though this evolution appears logical from a historical point view, it is anything but obvious from a technological point of view. The reason is at least threefold. Firstly, all materials are ever more operated close to their operational limits. Secondly, ever more technological disciplines are coming into play. Thirdly, all design aspects are strongly interlinked. Material science, power electronics, numerical optimization, rotor dynamics, thermodynamics, control theory, mechanical processing et al. are among the many linked disciplines key to neatly designing high-speed motor applications such as centrifugal compressors. In the presentation, these statements will be outlined and illustrated by practical examples.
