Hiroaki Toda
Electrical Steel Research Dept., Steel Research laboratory, JFE Steel Corporation

Abstract

Recently, there has been a growing need for improving motor efficiency in response to environmental problems such as global warming and energy problems. This leads to a strong demand for further improvement of non-oriented electrical steel sheets. In order to improve motor efficiency, it is important to use proper electrical steel sheets as core material. Therefore, it is desirable to estimate the effect of various electrical steels on the motor’s characteristics at the design stage. The existing JMAG material database has conventional JN series in thickness of 0.35 and 0.50 mm, and JNA series with low iron loss after stress relief annealing. A new database, which includes JNE series having a higher magnetic flux density than JN series, JNEH series of 0.20 mm thickness for high-frequency motors, 6.5% Si steel sheet, and gradient high Si steel sheet, will be released in the near future. The influence of magnetic properties of various non-oriented electrical steels on the motor efficiency and iron loss of a 6/4 SRM has been studied. This report also presents the calculation results of the motor iron loss based on FE analysis. The motor iron loss of SRM was calculated by applying different formula to each portion according to the classification of the flux density waveforms.