Research on the influence mechanism of harmonic components on the noise distribution characteristics of converter transformers

Abstract

In order to elucidate the sound source characteristics during the noise propagation process of converter transformers, a series of experimental studies were conducted based on finite element simulation and proportional prototype design of converter transformers. It was found that it was unreasonable to equate converter transformers with point sound sources in previous studies. On the contrary, it should be divided into dipole and multipole distribution characteristics. Meanwhile, research has found that the noise distribution of converter transformers exhibits dipole and dipole distribution characteristics under power frequency and harmonic excitation, respectively. The contribution of harmonic components at different frequencies in the formation process of bipolar sound sources was quantified through simulation and experiments, and the key harmonic frequencies for forming multipole sound sources were determined as paired combinations of 5, 7, 11, 13, 23, and 25. Based on the above research conclusions, a noise reduction approach for converter transformers based on bipolar and multipole boundary effects is proposed.

Keywords

• Converter transformer
• Harmonic
• Noise propagation
• Noise control