摘要
为了研究套管容性故障对频响曲线的影响,以频率响应分析法为理论基础,建立了检测变压器绕组变形的测试系统,以套管电容性故障为例,引入相关系数作为判据,对发生套管电容性故障的变压器进行测量,并从理论上分析了激励源位置分别为套管导杆和末屏时的频响曲线变化情况。试验结果表明:频率为1kHz^1MHz时,通过导杆注入扫频信号得到的频响曲线对套管电容性故障并不敏感,基本不会发生改变;利用末屏注入信号时,该故障对频响曲线的影响较大,会出现频响曲线全频段的幅值升高,并在频率为1~25kHz时最为明显,使得相关系数出现较大偏差,造成对变压器绕组状态的误判,且该变化与绕组故障时的情况并不相同,具有较强的可辨识性。
To investigate the influence of bushing capacitive fault on frequency response curves, a testing system for detecting transformer winding deformation based on frequency response analysis （FRA） is developed. The correlation coefficient is introduced as a criterion to evaluate the influence of bushing capacitive faults on transformer winding deformation diagnosis. Taking a transformer with capacitive faults in bushing as example, the changed frequency response curves are theoretically analyzed when excitation source is located at the bushing guide-bar and tap respectively. The results show that frequency response curves are insensitive to bushing capacitive faults in frequency range of 1 kHz- 1 MHz while the busing guide-bar is used as the signal injection port; the amplitudes of the frequency response curves increase significantly in the whole band, especially in the frequency range of 1- 25 kHz while the tap of bushing with capacitive faults is acted as the signal injection port, which usually leads to misjudgments of transformer winding deformation by the correlation coefficients of the transfer functions, and the frequency response curves caused by bushing capacitive fault are different from those caused by winding deformation.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2014年第2期62-68,共7页
Journal of Xi'an Jiaotong University
基金
国家电网公司科技资助项目(522722130397)
关键词
绕组变形
频率响应分析法
套管
电容性故障
winding deformation
frequency response analysis method
bushing
capacitive fault
