基于VFTO特性的变压器绕组变形在线检测方法

On-line Detection Method for Transformer Winding Deformation Based on Characteristics of VFTO

目前,变压器绕组变形的检测大多采用离线方式,需要变压器退出运行,降低了变压器的运行效率,存在一定的局限性。为能在线及时检测到绕组变形,结合频率响应分析原理,提出了基于特快速暂态过电压(Very Fast Transient Overvoltage,VFTO)特性的变压器绕组变形在线检测方法。利用变压器绕组在VFTO信号中高频成分冲击下体现的频率响应特性,测量绕组进线端的VFTO信号和绕组末端的响应信号,计算得到频率响应曲线,通过分析比较曲线中波峰、波谷的变化实现绕组变形的在线检测。仿真结果表明,该方法对绕组不同变形类型、程度和位置均体现出差异性和规律性,具有潜在的实用价值。

Off-line mode is mostly used in the detection of transformer winding deformation; however,it has some limitations. To detect winding deformation on-line and in time,an on-line detection method for transformer winding deformation based on characteristics of Very Fast Transient Overvoltage（ VFTO） is proposed by combining the principle of frequency response analysis. Frequency response characteristic of the winding which is under the impact of high frequency components in VFTO is utilized. The VFTO signal in the input end of transformer winding and the response signal in the terminal are measured,which are calculated to frequency response curves. On-line detection of winding deformation can be done by analyzing and comparing the variations of the response curves. The simulation results show that the method reveals diversities and regularities of different deformation types,location and degree and it is of great potential practical value.