基于中线电流注入的三电平有源电力滤波器中点平衡策略  

A Neutral Current Injection Based Neutral Point Potential Control Strategy for Neutral Point Clamping Based Tri-Level Shunt Active Power Filter

作　　者：胡健[1] 陈文宪 陈冬冬[1] 陈恒林[1] 陈国柱[1] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《电网技术》2014年第11期3160-3165,共6页Power System Technology

基　　金：国家自然科学基金项目(51177147)~~

摘　　要：对于中点箝位式三电平有源电力滤波器,建立了中线电流与中线电压的定量数学模型。基于上述模型,提出了一种三电平中点电位控制方法。通过引入表示中线电流与电容中点电位关系的系数,可以根据上下电容电压差直接计算出注入的中线电流的合理值。同时通过合理选择滤波器参数与采样频率,可以抑制该方法对于APF补偿效果的影响。仿真与实验研究结果表明,该方法在基本不影响补偿效果的同时可消除中点电位不平衡。A quantitative mathematical model for neutral current and neutral voltage in neutral point clamping（NPC） three-phase four-wire tri-level active power filter（AFP） is established.Based on the established model,a control method for neutral point potential of tri-level APF is proposed.Leading in a coefficient representing the relation between neutral current and neutral potential of capacitor,according to the voltage difference between upper capacitor and lower capacitor the reasonable value of neutral current to be injected can be calculated directly.Meanwhile,by means of reasonably choosing filter parameters and sampling frequency,the effect of the proposed control method on the compensation effect of APF can be suppressed.Results of simulation and experiments show that using the proposed method the neutral potential unbalance can be eliminated when the compensation effect of APF is basically not affected.

关 键 词：三电平 三相四线制 有源电力滤波器 中点电压控制 中线电流 

分 类 号：TM721[电气工程—电力系统及自动化]