Abstract: The magnetic properties of electrical steel sheet deteriorates due
to residual stress, which occurs during the manufacturing process. Therefore,
it is important to know the relationship between the magnetic property and the
residual stress in order to utilize electrical steel sheets effectively. This
paper presents the effect of residual stress on the magnetic properties of
motor cores in a rotating machine. First, the local residual stress
distribution of the motor core is measured using an X-ray stress measurement
system. Next, the magnetic properties of the motor cores for the different
residual stress distributions are measured using a single sheet tester. Based
on these results, the maximum permeability and magnetic power loss differed
depending on the sample, each of which had a different residual stress. In
addition, we attempt to measure the inductance of the motor core in order to
easily evaluate the magnetic property. The difference in the inductance of each
sample was obtained based on the excitation voltage and frequency measured
using an LCR meter. It is very useful to evaluate the inductance in order to
easily determinine the difference in the residual stress.
Keywords: Residual stress, motor core, magnetic property, inductance, magnetic power loss
