基于变压器铁芯接地线的电网故障暂态行波信号检测新方法

A novel method for power grid fault traveling wave detected based on the grounding line of transformer core

行波检测是影响行波定位精度的一个关键因素,提出通过行波传感器套接在变压器铁芯接地线,检测变压器所有出线线路发生故障时产生的暂态行波信号新方法。建立变压器的高频暂态模型,分析变压器线圈暂态静电感应过程,将变压器绕组和铁芯之间分布电容等效为一组电容链,通过测量变压器的铁芯接地线上暂态电流信号的幅值和能量值,检测电网故障暂态行波信号。EMTP仿真结果表明:所提的暂态行波信号检测方法能准确提取变压器高、中、低压侧所有出线的暂态行波信号,且行波传感器可带电安装,节省设备投资,便于推广。

The travelling wave detection is a key factor influencing the fault location precision. A method to extract transient traveling wave signal with a traveling wave sensor installed on the substation transformer core grounding line was proposed in this paper. The high frequency transient model of transformer was established, and the wave process of transformer windings was analyzed, then the distributed capacitance between the windings and core was equivalent to a group capacitance . The traveling wave could be detected by the amplitude and energy of the transformer core earthed current. EMTP simulation results showed that the transient traveling wave signal in any transmission line of transformer high, medium or low voltage side can be extracted only with a traveling wave senor installed on the core grounding line？ which saves investment and is convenient to use.