Power electronics broad application in power systems brings serious harmonic pollution . this paper introduces harmonic harm , the measure of restraining harmonic and the basic principle of filter 摘要电力电子装置的广泛应用，给电力系统造成了一定的谐波污染，文中简要论述谐波的危害、谐波的治理措施及无源滤波器和有源滤波器的基本原理。
Comparing with passive filters , apf have many advantages , which are not easily affected by system impedance and can be used to dynamically compensate harmonic . apf will play an important role in eliminating harmonics 有源电力滤波器技术与无源滤波器技术相比，具有受电网阻抗影响小、能够动态补偿等优点，将在治理谐波污染方面发挥主导作用。
The steady compensation characteristic and the damping resonance characteristic of the equipment are analyzed in detail , theoretic analyze and experiment results have verified the feasibility and the correctness of the proposed topology 仿真和实验结果表明该装置具有良好的稳态补偿特性，并且可以较好的抑制无源滤波器与电网阻抗之间的串并联谐振。
4 . the double dsp technique is introduced , and the furthermore the traditional fft analysis and nowaday theory of instantaneous reactive power is combined , thus the combined system of shunt passive filters and active power filters is designed 4 、采用双dsp芯片技术，将传统的频域分析fft计算与现代的瞬时无功功率理论相揉和，进行lc无源滤波器和并联型有源电力滤波器混合系统的设计。
The basic idea is that increasing the equivalent harmonic impedance of power network by valid control of active filter , in order to enhance the performance of passive filter and damp the resonance between the passive filter and the equivalent inductance of the power network 无源支路在补偿无功功率的同时还可以滤除因非线性负载产生的特征谐波电流，为了抑制无源支路跟电网等效电感产生的谐振现象以及改善无源滤波器的滤波性能，系统中采用谐振注入式有源滤波拓扑。
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。
In the last few years , the polution and harm of harmonic hi the power system is becoming more and more serious . the lc passive filter that is used widely ca n ' t satisfy the new demands of harmonic filter . the combined system of shunt lc passive filter and active power filter are put forward , and this paper focus on the following four aspects . 1 近年来，电力系统谐波的污染和危害日趋严重，而国内普遍使用的lc无源滤波器逐渐不能适应滤波的新要求，本文提出了与可变参数lc滤波器混合使用的并联型有源电力滤波器系统，并着重研究了以下几个主要问题： 1 、 lc无源滤波器(主要是高通滤波器)参数调节对阻抗特性和无功补偿的影响。
