考虑磁致伸缩效应电力变压器振动噪声的研究

Research on Vibration and Noise of Power Transformer Cores Including Magnetostriction Effects

硅钢片磁致伸缩是电力变压器产生振动噪声的主要原因,本文利用能量变分原理,建立了考虑电力变压器铁心磁致伸缩效应的三维磁-机械强耦合数值模型,应用有限元计算了三相三柱干式变压器空载条件下的磁场分布和铁心振动位移;在此基础上分析了铁心周围的声场分布。为了验证模型,对变压器铁心的振动和噪声分别进行了实验研究。理论计算与测量结果的比较证实了该强耦合模型的正确性,为在设计阶段计算变压器振动噪声大小、分布和寻求新的降噪措施,提供了理论依据和计算方法。

An important source of transformer noise is magnetostrictive vibration of the magnetic core. In order to calculate the vibration due to magnetostriction（MS）, magneto-mechanical strong coupled model for power transformer cores including anisotropic reluctivity tensor and MS is founded based on the energy variation principle. Using the proposed model, the magnetic flux and vibration of three-phase three-column transformer cores with no-load are calculated by the finite element method. And on the basis of the vibration calculation, the acoustic field around the transformer is analyzed. In order to verify the model, vibration and noise were studied experimentally. Numerical calculation results together with experimental results confirm the validity of the proposed method. Furthermore, this method which could help prediction the noise level in transformer design step and seek new denoise methods has great potential in the future application.