具有低谐波阻抗的三相四桥臂有源电力滤波器  

Three Phase Four Leg Active Power Filter with Low Harmonic Impedance

作　　者：田浩 陈坤燚 柯贤旺 黄佩贤 Tian Hao;Chen Kunyi;Ke Xianwang;Huang Peixian(College of Intelligent Systems Science and Engineering,Hubei Minzu University,Enshi,Hubei 445000,China)

机构地区：[1]湖北民族大学智能科学与工程学院,湖北恩施445000

出　　处：《机电工程技术》2023年第8期251-255,270,共6页Mechanical & Electrical Engineering Technology

基　　金：湖北民族大学高水平科研成果校内培育项目(PY22010)。

摘　　要：传统控制策略的有源电力滤波器在三相不平衡工况下无法快速精确检测谐波电流,会造成控制环节设计复杂以及滤波效果差的问题。为此,提出一种具有低谐波阻抗特性的三相四桥臂有源电力滤波器。通过建立三相四桥臂的平均开关模型在αβ0坐标下实现桥臂间的解耦控制。与传统的滤波器相比,该滤波器无需谐波检测环节,在三相不平衡工况下控制逆变器控制前三桥臂跟踪输出公共连接点基波正序电压,使滤波器相较负载侧呈高基波阻抗;同时,通过设计控制环节使滤波器谐波阻抗近似为0,使谐波全部通过逆变器支路流入大地,利用分流的原理实现滤波。与传统有源电力滤波器相比,该方法简化了滤波系统复杂程度同时降低了控制难度。在PSCAD软件中搭建了仿真模型。结果表明:在有源电力滤波器投切后,系统侧电流三相谐波含量从23.57%、25.38%、23.57%降低到了0.56%、0.82%、0.51%,系统侧电流基本为对称三相正弦波形,满足谐波抑制的国际标准。Traditional active power filters cannot quickly and accurately detect harmonic currents under three-phase unbalanced conditions,resulting in complex control design and poor filtering performance.Therefore,a three-phase four leg active power filter with low harmonic impedance characteristics is proposes.Decoupling control between bridge arms is achieved by establishing an averaged switch model of the three-phase four leg active power filter.Compared to traditional filters,this filter does not require harmonic detection and only needs to control the inverter to track and output the common link point fundamental voltage of the front three bridge arms,making the filter have a high fundamental impedance compared to the load side;at the same time,by designing the control link,the filter\s harmonic impedance is approximately zero,allowing all harmonics to flow into the ground through the inverter branch,and the filtering is realized by using the principle of shunt.The control link is simplified compared to traditional active power filters.A simulation model is built in PSCAD.The results show that after the switching,the three-phase harmonic current decreases from 23.57%,25.38%and 23.57%to 0.56%,0.82%and 0.51%,and the system side current is basically symmetric three-phase sine waveform,which meets the international standard of harmonic suppression.

关 键 词：有源电力滤波器 三相四桥臂逆变器 无谐波检测 

分 类 号：TM77[电气工程—电力系统及自动化]