小波变换在励磁涌流和短路电流识别中的应用

Wavelet Transform Applied to Identifying Magnetizing Inrush Current and Internal Fault Current

为了识别励磁涌流电流和内部故障电流,根据小波变换后励磁涌流在高频率段处呈现出明显的奇异性的特点,利用小波变换对变压器的励磁涌流模型和内部故障模型进行仿真分析,确定了基于一尺度下奇异值的小波判据,比较其高频段上能量的变化情况来识别励磁涌流和内部故障电流。结果表明,此方法可以对励磁涌流和内部故障电流进行良好识别。

In order to identify magnetizing inrush current and internal fault current, according to a clear singularity in the high frequency of the magnetizing inrush transformed by wavelet , using wavelet transform the magnetizing inrush current model and internal fault current model the simulation analysis is researched. A criterion based on the wavelet criterion is studied,which recognizes the magnetizing inrush current and the internal fault current by comparing with the both energy change in the high frequency sect. The results show that the transformer magnetizing inrush current and the internal fault current can be distinguish by this method.