三相并网逆变器LCL滤波器的简明设计

LCL滤波器以其较好的滤波性能被广泛地用于并网逆变器,但无阻尼时系统产生谐振,给系统的稳定性控制带来困难。文中在建立三相并网逆变器数学模型的基础上,采用基于d,q同步旋转坐标系的电网电压定向控制策略,利用被动阻尼抑制谐振提高了并网逆变器的稳定性能。文中给出了被动阻尼LCL滤波器的详细设计方法,并比较其与单L滤波器的滤波效果,运用Matlab/simulink建立系统模型并进行仿真,实现了单位功率因数并网。

A Concise Design of LCL Filter for Three-Phase Grid-Connected Inverter

LCL filter is widely used in grid-connected inverter for its good filtering performance.But under the undamped condition,resonance will be caused in the system,and then it can bring difficulties for the stability control of the system.On the basis of the mathematics model of three-phase grid-connected inverter,a novel approach was proposed in this paper,to adopt voltage directional power control which is based on d&q synchronization rotating reference frame,and inhabit resonance by passive damping to get better performance of the grid-connected inverter.This paper gives the detail design of passive damping LCL filter,and compares with the filtering effect of the single-L filter,builds system model by simulation in Matlab/Simulink and realizes unity factor to be grid-connected.