考虑波动系数筛选的谐波发射水平估计

摘要

In this paper,a new method to estimate the system harmonic impedance and harmonic voltage emission level is proposed considering volatility coefficient screening.First,based on the basic principle of fluctuation method,it can be inferred that the key to the improvement of the accuracy of fluctuation method is to filter out the harmonic samples when the background harmonic maintains stable.Second,through studying the correlation between the fluctuations of harmonic voltage and current at the point of common coupling,a model is built with the correlation coefficient in probability theory.Moreover,volatility coefficient is proposed as a screening index to measure the background harmonic fluctuation.Finally,the system harmonic impedance and harmonic voltage emission level can be estimated by the qualified samples after screening.Through the simulation of experimental circuit and the verification of practical engineering applications,it is proved that the proposed method is accurate and effective.%本文提出了一种考虑波动系数筛选的用于估计系统侧谐波阻抗及谐波电压发射水平的方法.首先,从波动量法的基本原理入手,分析得到筛选出背景谐波保持稳定时段内的谐波样本是提高波动量法精度的关键;其次,通过研究公共连接点处谐波电压和电流波动量的相关性,以概率论中的相关系数建立模型,提出以波动系数衡量背景谐波波动程度,且以此作为筛选指标,进而由筛选合格的有效样本估计系统谐波阻抗及谐波电压发射水平.通过实验电路的仿真分析和实际工程应用的验证,证明了所提方法的准确性和有效性.