极坐标图像法用于检测变压器绕组的微小辐向变形故障

频率响应分析法一直以来被认为是诊断电力变压器绕组变形故障最具潜力的方式,然而,现有频率响应分析法大多仅利用频率响应的幅值信息,而忽略了其相位变化的特性,针对某些故障类型,例如绕组的微小辐向变形故障,仅利用幅值信息的方法,故障诊断的灵敏度并不高。因此,文中提出一种新的极坐标图像法,利用频率响应构造极坐标图像,进而辅助诊断绕组变形故障。通过开展绕组等效电路模型的算例分析,结论证实在传统频率响应分析法不能反映绕组微小辐向变形故障时,此提出的方法可能更有效地检测出绕组故障,极坐标图像法具有更高的诊断灵敏度。

Detecting transformer winding minor radial deformation fault by polar image

Frequency response analysis is always considered to be a prospective method to diagnose power transformer winding deformation fault,however,the most existing frequency response analysis just uses the amplitude information of frequency response,and ignores the characteristic of phase variation.However,as for some types of winding fault,such as winding minor radial deformation,the sensitivity of diagnosing fault is not high enough.Thus,this paper proposes a new polar image method,the frequency response is used to construct the polar image,which assists to diagnose winding deformation fault.A case study of winding equivalent electrical model is carried out,the result demonstrates that the proposed method may detect winding fault more effectively,while the normal frequency response analysis can't reflect the winding minor radial deformation fault,the polar image method has higher sensitivity of diagnosis.