基于偶极等效声源的特高压变压器有源降噪方法研究

Research on Active Noise Reduction of Ultra High Voltage Transformer Based on Dipole Equivalent Acoustic Source

有源降噪技术主要基于声波干涉相消原理,因此初级声源和次级声源的声场传播特性及其声波相干作用导致的声场分布变化规律的研究对有源降噪的系统设计及次级声源的布局至关重要。在实验室进行变压器有源降噪实验时,通常采用扬声器来模拟变压器噪声,因此扬声器等效模型的选择很关键。等效为点声源模型简单方便,但误差较大。该文选取偶极声源模型作为扬声器的等效模型,并以实测特高压变压器噪声特性为基础,分别对扬声器等效为点声源模型和偶极声源模型的声场干涉特性进行仿真和实验验证。实验结果表明,偶极声源模型比点声源模型更符合扬声器实际的声辐射特性。

Active noise reduction technique is mainly based on the principle of acoustic interference cancellation.Therefore,it is very important for the active noise reduction and the placement of secondary sound sources to study the sound propagation characteristics of the primary and secondary sources and the variation of the sound field distribution caused by the coherent effects of the acoustic wave.In the laboratory,the loudspeaker is used to simulate transformer noise when it is used in active noise reduction experiments.Thus,the choice of speaker equivalent model is critical.Although the point source equivalent model is simple and convenient,the error is large.The dipole source was chosen as the equivalent model of the loudspeaker in this paper.Based on the measured noise characteristics of ultra high voltage(UHV)transformer,the acoustic interference characteristics of the speaker that was equivalent to both point source model and dipole source model was analysed through simulation and experiment.The experimental results show that the dipole acoustic source model is more in line with the actual acoustic radiation characteristics of the speaker than the point source model.