The active power filter can compensate the harmonic of variety in magnitude and frequency . so we adopt active power filter to restrain harmonic of electric arc furnace , and a new method of detection adaptive electric arc furnace is presented , the result of simulation indicate that the method is proper 而有源滤波器能对大小和频率都变化的谐波进行实时补偿，所以本文研究了将有源滤波器用于电弧炉系统谐波抑制的方法，并提山了一种针对电弧炉系统的谐波检测方法。
To put into operation a large amount of non - linear load , make in harmony wave of rural power grids serious becoming in pollution , pass to rural local electric wire netting main in harmony analysis of wave source , put forward in order to restrain from insert rural power grids in harmony wave source voltage total in harmony wave distortion rate and the containing rate change last device number pulsating for increase of goal , increase the pulse of the current change device and install light specified value electricity active wave filter mix with passive wave filter near the harmonics source to control the wave in harmony 摘要大量非线性负荷的投运，使农村电网的谐波污染日趋严重，通过对农村地方电网主要谐波源的分析，最终提出了以限制接入农村电网的谐波源的电压总谐波畸变率和各次谐波电压含有率为目标的增加换流装置脉动数，以及在谐波源附近装设小额定值的电力有源滤波器配以无源滤波器的混合型电力滤波方式，以进行谐波治理。
According to the characters of the power harmonic , a kind of self - adaptive harmonic detection method based on in - phase correlation filtering is presented , which is clear and concise in thinking . by this method the low - pass filter can be designed easily , and by using the multiresolution and self - adaptive technique the difficulties of harmonic detection with low variable fundamental frequency and no voltage reference are worked out , which contributes much to the implementation of harmonic suppression 该方法思路清晰、简洁，并能方便有源滤波器( apf )中低通滤波器设计，同时采用多分辨率和自适应滤波方法，解决了基波频率低且变化、无明显电压基准可寻的复杂供电系统谐波检测的难题，为谐波抑制的实施奠定了基础。
This method can inspect the harmonic component and reactive power immediately . based on this prototype , matlab , which is a simulated tool for power system , is used to prove it . experimental results are presented to conform the effectiveness of the apr 本设计用先进的仿真软件工具matlab中的电力系统仿真工具箱对基于这种方法的有源滤波器进行仿真，仿真结果表明基于瞬时无功功率理论设计的有源滤波器装置能够有效检测出谐波分量，并可以抑制谐波分量和进行无功补偿。
At last the components of the system are modeled and simulated with matlab software . the simulation results indicate that the combined system can reduce the capacity of apf effectively , detecting the harmonic current effectively , compensating harmonic current effectively 结果表明，对单位容量的谐波源，采用与可变参数lc滤波器混合使用的并联型有源电力滤波器系统，能够有效地减少有源滤波器的容量，有效地检测出高次谐波分量，并进行谐波补偿，使系统的电流波形基本保持正弦。
We design the qmf based on the criteria of minimum frequency bandwidth and the qmf that possess linear phase , and give a example of a signal decomposed and restructured . 4 . in the research of channel dropping filters , we use 5 rank butterworth filter to approach the digital filter . we design lc unpower netwok and rc power network . we manufacture lc lowpass and highpass filter ， and test their performance ; we simulate the appliance of the channel dropping filters in the system 4 .在频带分割滤波器的设计方法中，用5阶巴特沃斯滤波器逼近最小频宽正交镜像滤波器，对无源和有源滤波器进行了仿真设计；设计并制作了无源lc低通和高通滤波器，测试了它们的性能；并对分割滤波器在系统中的应用进行了计算机仿真。
Combined active power filter and reactive power filter make up hybrid active power filter which not only reduce the cost but also have good harmonics compensation effect , so hybrid active power filter reaches a practical purpose . the paper introduces the concept of harmonics 、 its harm to power grid and limitation of harmonics voltage and current harmonics , and it also demonstrates the necessity of eliminate harmonics , and briefly introduces several methods to eliminate harmonics and research of both here and abroad 将有源电力滤波器与无源电力滤波器相结合,构成混合有源滤波器,取两者之长,补两者之短,既可以降低谐波补偿系统的成本,也可以有良好的谐波补偿效果,从而达到混合有源滤波器实用的目的。
