Influence of Mechanical Stress on the Magnetic Properties of Electrical Steel Sheets

  test bench Copyright: IEM

Different mechanical stresses affect the electrical steel sheets in electrical machines during operation. For example, centrifugal forces on the rotor, stresses due to shrink fitting or electromagnetic forces are considered. Mechanical stress influences the magnetic properties of ferromagnetic materials and take an effect on the magnetic flux path and iron losses. A single sheet tester measures the variations of hysteresis curves or losses of electrical steel sheets which are loaded by tensile and compressive stresses. Material models are derived from the results and integrated into the FEM calculation to allow a more exact simulation of the flux distribution with additional influence of mechanical stresses.