基于LMD算法的电压闪变参数识别新方法

New Method in Voltage Flicker Parameter Identification Based on Local Mean Decomposition Algorithm

为了实现电压闪变参数的精确识别,针对采用常规算法求取的电压闪变的调幅波、间谐波参数波动大的问题,首次提出了将局部均值分解(LMD)算法应用于电压闪变参数识别.选取典型的电压闪变算例,应用LMD算法和HHT算法进行仿真对比,结果表明,LMD通过除以包络函数得到PF,"筛分"次数较少,端点效应较小,所求的闪变参数在稳态时基本不变化.该方法步骤简单、运算速度快,证明了LMD算法的可行性与准确性.

To realize high-accuracy measurement parameters of voltage flicker,focusing on the amplitude modulationwave and inter-harmonics parameter fluctuation problem in voltage flicker based on conventional algorithm,thelocal mean decomposition（LMD）algorithm is adopted to analyze voltage flicker parameter identification in powersystem for the first time. The paper selects typical voltage flicker signal,compares the simulation results by LMDalgorithm and HHT algorithm. Simulation results show that because the LMD algorithm gets a PF by dividing theenvelope function and the number of＂Screening＂is relatively less,the end effect is small. The flicker parameters inthe steady state basically do not change based on LMD. LMD is superiority,the method is simple,rapid and highaccuracy. The results show LMD algorithm is feasible and accurate.