基于模态叠加法的变压器绕组振动特性分析

Vibration characteristics analysis of transformer windings based on mode superposition method

变压器绕组振动极易导致绕组机械形变,从而影响到设备乃至于电力系统的安全稳定运行。文中旨在更便捷的研究变压器绕组的振动特性,首先,利用多自由度系统力学理论,基于模态叠加法建立绕组振动位移响应的解析模型,该模型的刚度系数和激励参数可以反映绕组多种工况的振动特性,文中主要分析了螺栓预紧力和电磁力两个典型因素对绕组振动特性的影响。并以一台10 kV三相变压器为例,设计绕组松动的锤击试验和在线振动监测试验,试验分析结果与解析模型分析结论吻合,验证了解析模型的有效性。文中研究内容为变压器绕组结构设计和状态评估提供了新的思路。

Intensified vibration of the transformer windings can easily lead to mechanical deformation of the windings,thus affecting the safe and stable operation of the equipment and even the power system.Therefore,it is necessary to analyze their vibration characteristics in various conditions.Firstly,based on the mechanics theory of multi-degree-of-freedom system,we establish the analytical model of winding vibration displacement response based on vibration mode superposition method.Then,we applied this model to analyze the effects of two typical factors of pre-compression and electromagnetic force on the vibration characteristics of the winding.Taking a 10 kV three-phase transformer as an example,the hammer test and the online vibration monitoring test of loose winding are completed under different working conditions.The experimental results are in accordance with the analytical model.The experimental results verify the validity of the analytical model and provide a new idea for the structure design and state evaluation of the transformer winding.