文档介绍：三电平中点箝位型逆变器中点电压平衡和控制方法研究*
胡存刚1 王群京1,2 严辉3 杨益3
(1. 合肥工业大学电气与自动化工程学院, 合肥 230009; 2. 安徽大学电子科学与技术学院, 合肥 230039;
3. 安徽建筑工业学院电子与信息工程学院, 合肥 230022)
摘要: 建立了三电平中点箝位型逆变器中点电压的数学模型; 分析了在不同的负载条件下, 传统的最近三矢量合成方法中点电压存在不能平衡的区域; 利用合成空间矢量的调制方法, 实现了对中点电压的有效控制。为了在扇区切换时输出矢量平稳过渡, 提出了在每个大区内全部采用相同首发小矢量的方法。用MATLAB/Simulink仿真研究了中点电压平衡控制的效果, 并用MOSFET搭建了三电平逆变器实验电路模型, 对中点电压平衡控制效果进行了验证。实验结果证明了基于合成空间矢量的三电平NPC逆变器中点电压平衡控制方法的有效性。
关键词: 中点箝位型逆变器;空间矢量调制;中点电压平衡;合成空间矢量
中图分类号: TM464 文献标识码: A 国家标准学科分类代码:
Research on neutral-point potential balancing and control method
for three-level NPC inverter
Hu Cungang1 Wang Qunjing1,2 Yan hui3 Yang Yi3
(1. Hefei University of Technology, Hefei 230009, China; 2. Anhui University, Hefei 230039, China;
3. Anhui Institute of Architecture & Industry, Hefei 230022, China )
Abstract: A significant problem with neutral-point-clamped three-level inverters is the fluctuation in the neutral-point voltage. The mathematics model of neutral-point potential is developed while the neutral-point potential is unbalanced. In this paper the limitations of neutral-point potential balancing problem for different loading conditions of three-level neutral-point-clamped inverters is explored. And a novel modulation approach for plete control of the neutral-point potential is introduced. The new modulation approach, which bases on the virtual space vector concept, guarantees the balancing o