基于瞬时无功功率的改进型谐波电流检测法  

Improved Method of Detecting Harmonic Currents Based on Instantaneous Reactive Power Theory

作　　者：成立[1] 范木宏[1] 王振宇[1] 尹星[1] 刘星桥[1] 祝俊[1] 

机构地区：[1]江苏大学电气与信息工程学院,镇江212013

出　　处：《高电压技术》2007年第4期46-49,共4页High Voltage Engineering

基　　金：国家高技术研究发展计划(2004AA2Z4010)~~

摘　　要：为了改善传统的有源电力滤波器(APF)的快速检测和实时补偿性能,提出了一种基于瞬时无功功率理论的改进型ip、iq检测法。该方法通过建模和分析,用简单的积分、延时和增益环节代替传统的低通滤波器,将检测方法总延时从1个电源周期减少到1/6个电源周期。该方法还可推广应用到单相电路、三相四线制和三相不平衡负载等场合。运用MATLAB软件进行仿真的结果表明:该方法在电网电压对称有畸变或对称无畸变时都能跟踪谐波,准确检测出谐波和无功电流,并可将每个电源周期的检测方法总延时从0.02s减少到约0.0033s,从而验证了该方法满足电力系统中APF的实时测量要求。Quickly and accurately detecting the harmonic currents is the precondition to improve the electricity supply and to ensure the normal operation of the power system. In order to improve real-time reactive power compensation and quick-response characteristics of conventional active power filter（APF} at present,this paper proposed a kind of improved ip,iq detecting method, which is based on instantaneous reactive power theory. By means of building a kind of detecting circuit model and analyzing the model, this method, applied in APF, simply replaced the conventional lower-pass filter（LPF） with 2 integrals, 2 time-delay circuits and 2 amplifiers, thus reducing the delay-time from one cycle to 1/6 cycle. Meanwhile, the model could also be applied to a single-phase circuit, three-phase four-wire circuit and three-phase unbalanced load system. For example,when applied to a single-phase circuit,its total detecting delay-time within a supply period was only 5T/6. With the MATLAB simulation results,it has been proved that this method can quickly and accurately detect the harmonic and reactive power currents in the power system with symmetry and distortion voltage or with symmetry and no distortion voltage, and that it can track the harmonic currents,and that the total delay-time of the method within a period even can be reduced from 0.02 second to 0. 0033 second. So this method can meet the real-time detecting demand in the power system.

关 键 词：有源电力滤波器 低通滤波器 谐波电流 瞬时无功功率 电力系统 

分 类 号：TM933.1[电气工程—电力电子与电力传动]