【摘要】 提出了在谐波存在时,基于有效值和小波变换检测电压跌落信号参数的方法。首先,利用小波变换的分频特点,提取信号的基频成分;然后,计算基频成分的有效值,根据其有效值曲线确定电压跌落发生的大致区间;最后,根据信号经小波变换分解得到的高频部分精确锁定电压跌落的准确起止时刻,并根据有效值曲线计算电压跌落幅度。仿真和实测结果表明了该方法的可行性和有效性。更多还原

【Abstract】 A method based on RMS and wavelet transforms to detect voltage sag signal on the condition of existing harmonics was proposed.Firstly,the base frequency component of signal was extracted by wavelet transform because of its characteristic of frequency base partition.Secondly,RMS value of base frequency component was computed and the approximate bound of voltage sag happening was determined by curve of RMS value.Lastly,the accurate beginning and end moment of voltage sag was determined by the highfrequency parts which were derived by wavelet decomposition and sag amplitude was computed by curve of RMS value.The results from simulation and tests show that the proposed method is feasible and effective.更多还原