Simulation and Experimental Verification of Vibration and Noise Characteristics of Nanocrystalline High-Frequency Transformer

A high-frequency transformer (HFT) is the core component of a power electronic transformer, but the vibration and noise during normal operation of HFTs are severe. Therefore, this article investigates the vibration noise characteristics of HFT. Firstly, the vibration mechanism of HFT is studied, the electromagnetic force models causing HFT vibration are deduced, and the electromagnetic-mechanical-acoustic multiphysical field coupling model of HFT is established. Then, the vibration and noise characteristics of HFT under the excitation of sinusoidal and square wave are studied and analyzed based on the model. The results show that when the excitation frequency is 5 kHz, the dominant vibration frequency is 10 kHz for sinusoidal excitation. For square wave excitation, the dominant frequencies are 10, 20, and 30 kHz, with a sound pressure of 26.5 Pa, surpassing the 12.9 Pa observed under sinusoidal excitation. Finally, a vibration and noise experimental platform of HFT is built to verify the model, and vibration noise reduction methods for HFT are proposed, including increasing prestress and avoiding the presence of air gaps in the structure. The research results provide a theoretical and experimental basis for the magnetic-mechanical-acoustic multiphysical field coupling and vibration noise reduction of HFTs.