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This paper analyzes the relationship between the experimentally determined magnetostriction of grain-oriented electrical steel (GOES) coils and the no-load noise of power transformers (PT). The main source of a PT's no-load noise is the magnetostrictive vibration of the magnetic core built with stacked GOES sheets. With an in-house measurement system, in which steel coils with a mass of up to 6000 kg is measured, differences in the GOES materials’ magnetostriction were identified. In this paper, we analyze the flux dependent behavior and harmonic composition of the magnetostrictive properties of different steel coils. Based on the identified differences in the steel coils’ magnetostriction, two experimental studies with PTs are provided showing exemplary results. The first study shows initial findings of the relationship between the magnetostriction of the deployed steel coils and the emitted no-load noise of model transformers. In a second study, the aforementioned investigations were extended with measurements of large power transformers. Both studies cover a correlation and performance analysis including comparisons of the noise-related GOES certificate value B8 (also known as B800 value). [ABSTRACT FROM AUTHOR]

This paper presents a new method for measuring the specific losses and magnetostriction of grain-oriented electrical steel coils of up to 6000 kg. Since large power transformer (LPT) core manufacturers are mainly supplied with entire steel coils, a fast incoming goods inspection is desirable. The proposed method identifies the specific losses of the entire steel coil. In addition, we measured the magnetostriction of the coiled material, which in turn enabled us to classify the main property for LPT no-load noise. Furthermore, we show the structure and setup of the developed coil measurement system. We provide an explanation of the measurement technique and identify its requirements. Exemplary results of specific power losses and magnetostriction of steel coils are provided, and the reproducibility of the results is shown. [ABSTRACT FROM AUTHOR]