Comparison of magnetostriction models for use in calculations of vibrations in magnetic cores

Abstract

In this paper, the vibrations of the magnetic cores of power transformers due to magnetostriction are studied. To achieve this, a magnetostriction model based on magnetostriction measurements is needed. Two different magnetostriction models are compared, and their advantages and drawbacks are discussed. The first model is easy to implement, but does not include the hysteresis and the frequency dependency of the magnetostriction. To include these effects, a second model has been developed. This model is more difficult to implement and requires more magnetostriction measurements. As an application, the vibrations of a small power transformer are calculated using both models. By comparing the results, it is shown that the inclusion of hysteresis in the magnetostriction model has a significant impact on the calculated results for the vibrations of the transformer. © 2008 IEEE.