Design aspects of circumferentially cooled frameless machines

An innovative method of direct stator lamination cooling (air cooling) for electrical machines is presented. Particular aspects of stator design concerning electromagnetic, thermal and fluid mechanical effects are discussed. The paper provides an overview of interdisciplinary research in the field of novel cooling techniques for electrical machines. A combination of analytical and numerical approaches is used to predict the magnetic core resistance and the air flow characteristics and to calculate values of the components of equivalent networks. A planned experiment for the verification of magnetic calculation results is presented.