为了进一步提高输电线路行波故障定位精度,提出了一种基于局域均值分解(Local Mean Decomposition,LMD)与差分熵(Difference-entropy,DE)的输电线路行波检测方法,首先利用局部均值分解方法对电压线模分量进行分解,得到多个乘积函数(PF分量),然后利用差分熵度量最高频乘积函数(PF1分量)的突变信息,从而确定电压行波波头的到达时刻。最后,基于双端行波故障定位原理求出故障距离,对不同故障情况进行了仿真分析,并与小波变换以及希尔伯特黄变换进行了比较,仿真结果表明,该行波检测方法具有较好的波头检测效果,相对于目前存在的故障定位方法的定位精度有了进一步提高。
英文摘要:
In order to further improve the transmission line traveling wave fault location accuracy; This paper proposes a traveling wave detecting method for Transmission Lines based both on the LMD(Local Mean Decomposition)and DE( Difference-entropy ), First, we"d like to get the PF component of the decomposed signal with the LMD. Second, we prefer to obtain the signal mutation quantity information with the help of DE. And finally, we realize the fault distance using double terminal traveling wave fault location principle. After dealing with different malfunction conditions, And compares it with the wavelet transform and the Hilbert Huang Transform,the simulations show a better adaptability, a better result of wave head detection, and a higher positioning accuracy compared with the other traditional method.