考虑磁致收缩的750 kV电抗器的噪声计算

Abstract

电抗器噪声作为变电站噪声的主要来源之一，对于变电站外部声环境有重大影响。研究电抗器噪声对于电抗器的降噪分析具有重要意义。本文通过对750 kV甘肃永登变电站并联电抗器噪声声场分布的现场测量，得到了电抗器周围声场的干涉与衰减特性。并基于有限元法建立了并联电抗器的电磁、结构、声场仿真计算模型，通过时域电磁场分析得到了电抗器铁心与线圈中的磁场分布，将磁场所引起的铁心饼和线圈中的电磁力以及铁心中产生的磁致伸缩效应作为激励施加给铁心和线圈，通过振动分析得到铁心和线圈表面各节点的振动加速度，并将其作为声场分析的边界条件，最终得到电抗器噪声声场分布情况。将仿真结果与实测值进行对比分析，最大误差不超过15%，验证了有限元模型的可行性，为电抗器噪声预测及降噪措施提供了理论依据及控制方法。 Reactor noise, as one of the main sources of substation noise, has a significant impact on the ex-ternal acoustic environment of the substation. It is very important to study reactor noise for the noise reduction analysis of the reactor. In this paper, the interference and attenuation character-istics of the acoustic field around the reactor are obtained by field measurement of the noise field distribution of the shunt reactors in the 750 kV Gansu Yongdeng substation. The simulation calculation model of electromagnetism, structure and acoustic field of the reactor is established based on the finite element method. The magnetic field distribution of the core and the coil of the reactor is obtained by the time-domain electromagnetic field analysis. The electromagnetic force between the core cakes and coil and the magnetostrictive effect in the iron core caused by the magnetic field are applied as excitation to the core and the coil. The vibration acceleration of each node on the core and coil surface is obtained by vibration analysis, which is used as the boundary condition of the sound field analysis, and finally the noise field distribution of the reactor is obtained. The simulation results are compared with the measured values, and the maximum error is less than 15%. The feasibility of the finite element model is verified, which provides the theoretical basis and control method for the reactor noise prediction and noise reduction.