变压器去耦覆盖层降噪技术研究

Research on Noise Reduction Technology of Transformer Decoupling Coating

传统的低噪声变压器研究主要围绕着降低铁心磁通密度方面开展,但该技术因耗材多、成本高难以普及推广应用。文中基于吸声降噪原理,提出了在变压器内壁增加吸声装置调整变压器箱体声阻抗方法来实现降噪目的,并对声阻抗变化前后的变压器噪声特性进行了模拟仿真分析,计算结果表明,适当调整变压器箱体声阻抗后,变压器箱体外噪声可明显降低,声压最小降幅为5 d B。随后借鉴平板吸声器调整声阻抗降噪思路,研制了变压器去耦覆盖层面板,该面板采用模块化设计,多块去耦板独立组装敷设在变压器内壁,并通过球形阻尼器连接在一起。同时开展了变压器噪声测试,结果显示安装去耦覆盖层面板后,测点声压级明显降低,降幅可达7.1 dB(A)。

The research of traditional low-noise transformers mainly revolves around reducing the magnetic flux density of the core,but this technology is difficult to be popularized and applied due to its complex process and high cost.Based on the principle of sound absorption and noise reduction,a method of adding a sound absorption device on the inner wall of the transformer to adjust the acoustic impedance of the transformer box so to achieve the purpose of noise reduction is proposed in this paper. The noise characteristics of the transformer before and after the acoustic impedance change are simulated and analyzed. The calculation results show that after appropriate adjustment of the acoustic impedance of the transformer tank,the noise outside the transformer tank can be significantly reduced and the minimum sound pressure drop is 5 dB.Then,a transformer decoupling coating panel with the help of flat plate acoustic absorber to adjust acoustic impedance and noise reduction is developed. The panel adopts a modular design and multiple decoupling plates are independently assembled and laid on the inner wall of the transformer and connected together by a spherical damper. Meanwhile,the transformer sound insulation test is carried out. The results show that after installing the multi-frequency resonance decoupling cover,the sound pressure level of the measuring point is significantly reduced by 7.1 dB(A).