Basic study of loss reduction effect by Stator‐Tooth slits in turbine generators. comparison between calculated results of generators and basic experiments

In this study, we investigate the loss reduction effect by stator-teeth slits in turbine generators on the basis of electromagnetic field analysis and basic experiments. First, the loss reduction effect in the generator is estimated by the 3D finite element method and the theoretical solution of eddy current loss. Next, an experiment using a simple model that simulates the stator-core ends of the turbine generator is carried out. It is clarified that the loss reduction effect by the slits depends on the frequency, flux density, and permeability of the stator teeth because the loss reduction effect weakens with the skin effect. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(3): 17–25, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22345