电缆绕组变压器轴向振动模态特性的分析研究

建立了分析电缆绕组变压器振动特性的单线匝体单元有限元模型,利用"同振型一阶固有频率相等"的原则,得到了单线匝单自由度集中参数模型.将各线匝集中参数单元串联,即可得到轴向振动的等效网络模型.选择线匝轴向振动位移为自由度,列出了自由振动的微分方程,求解方程可以得到线圈的固有频率和对应的振型.讨论了线圈固有频率与线圈匝数、预紧压强、单匝固有振动频率的关系,为限制轴向振动提供了参考依据.

The Study of Modal Property on Axial Vibration of Power Transformer with XLPE Cable Winding

The model of solid finite element for analyzing vibration of single turn of power transformer with XLPE cable windings is set up. Based on the equal fundamental of first-order natural frequency and same mode shape, the lumped parameter model of single DOF for single turn was obtained. While the lumped elements are linked along axial direction, the vibrating model along axial direction can be given. The displacements of axial vibrating are selected as DOFs, so the differential vibrating equation is presented. Solving the equation, the natural frequency and corresponding mode shape can be obtained. At last, the relationships among natural frequency of winding and turn number, prepress, natural frequency of single turn are discussed, then an approach on weakening vibrating along axial direction is given.