三电平并网逆变器结构优化及中点电压控制  

Structural Optimization for Three-level Grid-connected Inverter and Neutral Point Potential Control

作　　者：吴雷[1] 徐鹏[1] 

机构地区：[1]江南大学,电气自动化研究所,江苏无锡214122

出　　处：《电力电子技术》2016年第6期9-12,共4页Power Electronics

基　　金：江苏省产学研创新项目(BY2012069)~~

摘　　要：将三电平并网逆变器的LCL滤波器电容公共点与直流侧中点相连可有效抑制共模电流,但易引发共模谐振,产生过大中线电流,加剧中点电压波动。首先优化滤波器结构解耦共模差模回路,减小中线电流;其次针对优化结构提出新的中点电压控制策略,最大程度消除中点电压波动;最后,通过仿真与实验验证了滤波器设计及控制策略的有效性。Linking the capacitor neutral point of LCL filter for three-level inverter back to the DC midpoint directly has an advantage of leakage current deduction.But it also brings common-mode resonance and large link-line current virtual value,which exacerbate midpoint voltage fluctuations.Firstly,the common-mode and differential-mode models are developed to optimize the filter structure,which leads to the reduction of link-line current.Aimed at optimized structural, new neutral point potential control strategies are proposed to eliminate midpoint voltage fluctuations to the greatest extent.Finally, the simulation and experiment results prove the validity of filter design and control strategy.

关 键 词：三电平逆变器 结构优化 中点电压控制 

分 类 号：TM464[电气工程—电器]