脉冲频率响应法检测绕组故障仿真分析

Simulation Analysis on the Feasibility of Transformers Winding Fault Detection Based on Impulse Signal Wave Response

变压器故障中比较常见的一种现象为绕组变形,该故障影响恶劣。检测变压器故障类型或者绕组的变形程度,对于故障的发展、绕组变形进一步恶化,保障电网的安全稳定运行具有深远意义。总结了绕组变形检测的常用方法,并提出了一种利用方波脉冲作为注入信号,检测绕组故障的新思路。并通过PSPICE仿真试验,验证了该方法的有效性。通过对比正弦扫频信号、双指数波信号和方波信号,理论分析方波脉冲信号具有检测频率宽,幅值高,操作简单等优点,得出其更适宜作为检测绕组变形的注入信号;在PSPICE中建立绕组的高频等效模型,通过改变绕组等效模型中对地电容和纵向电容,观察故障前后绕组的频响曲线,验证方波脉冲检测绕组变形的有效性。研究结果可对变压器故障检测方法提供参考。

Winding deformation is one of the most common types of transformer faults. It is important to detect the fault type and the degree of deformation in time,and to prevent the further deterioration of deformation and to ensure the stable operation of the transformer. This paper summarizes the common methods of winding deformation detection,and puts forward a new way to detect the faults by using the square wave pulse as the injection signal. And through PSPICE simulation and field test,the effectiveness of the method is verified. The main content of the paper is as follows： by contrasting sine sweep frequency signal and double exponential wave and square wave signal,it finds that square wave signal has the advantages of wide detection frequency,high amplitude,easy operation,and is more suitable to use the injected signal for detecting winding deformation; then the high frequency equivalent model of winding is established in PSPICE,and by changing the series capacitance and the ground capacitance,it is proved that the square pulse is effective on detecting the slight deformation. Research results can provide certain references for the measurements of transformer faults detection.