Magnetostriction and the Influence of Harmonics in Flux Density in Electrical Steel

Measurement of magnetostriction harmonics under stress is beneficial to clarify the relationship between magnetostriction and transformer noise. In this paper, a magntetostriction measuring system with small uncertainty is developed to measure the magnetostriction under a stress of ±20 MPa. The magnetostriction under sinusoidal and non-sinusoidal flux densities can be measured by digital waveform control. The components of magnetostriction harmonics and specific power loss at different percentages of the third harmonic in flux density and phase delay of the third harmonic with respect to the fundamental harmonic are investigated.