基于磁致伸缩力计算的变压器电磁振动研究

Study on Electromagnetic Vibration of Transformers Based on Magnetostrictive Force Calculation

摘要: 众所周知，磁致伸缩是电力变压器铁芯振动的主要原因。因此，如何实现磁致伸缩效应等效是决定电磁振动计算精度的重要因素。为了提高铁芯电磁振动的计算精度，本文计算了铁芯的磁致伸缩等效力。铁芯的磁致伸缩特性是力计算的数据基础。为此，首先测量了硅钢片的磁化强度和磁致伸缩特性。在实测数据的基础上，分析了铁芯的磁场，进一步精确计算了铁芯的磁致伸缩等效力。将等效力和电磁力同时加载到铁芯振动计算中，可得到铁芯电磁振动分析结果。最后测量了铁芯的振动。将测量结果与磁致伸缩等效力计算结果和传统初始应变法计算结果进行了比较。结果表明，仅计算磁致伸缩效应可以提高铁芯电磁振动的计算精度。

Abstract: It is well known that magnetostriction is the main cause of vibration of the power transformer core. Therefore, how to achieve magnetostrictive effect equivalence is the important factor that determines the accuracy of electromagnetic vibration calculation. To improve the calculation accuracy of electromagnetic vibration of iron cores, the magnetostrictive equivalent force of the iron core is calculated separately in this paper. The magnetostrictive property of the iron core is the data basis for force calculation. Therefore, the magnetization and magnetostrictive characteristics of silicon steel sheets are measured firstly. Based on the measured data, the magnetic field of iron core is analyzed, and then the magnetostrictive equivalent force of the iron core is further calculated precisely. The equivalent force and electromagnetic force are simultaneously loaded into the calculation of iron core vibration, and the results of core electromagnetic vibration analysis can be obtained. And the vibration of the core is measured at last. The measured results are compared with the results of calculation that include two parts, one is calculated with magnetostrictive equivalent force and the other with the traditional initial strain method. The results showed that the calculation accuracy of electromagnetic vibration of the iron core can be improved by calculating the magnetostrictive effect alone.