振动频响法VFRA在主变绕组变形检测中的应用研究

VFRA Application to the Detection of Main Transformer Winding Deformation

阐述了振动频响法是利用变压器绕组机械频响函数检测绕组变形的方法。验证了该方法具有良好的重复性,在A、B、C三相分别模拟轴向预紧力下降,幅向受力改变,轴向垫块脱落与幅向变形的故障,通过图像对比和计算说明振动频响法对绕组变形故障反应十分敏感,故障前后频响曲线相关系数最高为0.99,与传统方法相比有明显的优势。

Vibration frequency response analysis （VFRA） is a new method to detect the transformer winding deformation by means of the mechanical frequency response function. This paper verifies the repeatability of VFRA. Then three kinds of winding deformation failures （ axial preload decline, crosswise force change, and axial cushion block off and crosswise deformation） are simulated in the phase of A, B and C respectively. Comparison of images and computation show that VFRA is very sensitive to the winding deformation. The maximum correlation coefficient of vibration frequency response curve is 0. 99, which proves VFRA to be obviously superior to the traditional method.