三电平NPC逆变器改进虚拟空间矢量调制策略  

Improved Virtual Space Vector Modulation Strategy for Three-level NPC inverter

作　　者：赵起问 李俊杰[1] 姜建国[1] ZHAO Qi-wen;LI Jun-jie;JIANG Jian-guo(Key Lab of Power Transmission and Transformation of Ministry of Education,Shanghai Jiao Tong University,Shanghai 200030,China)

机构地区：[1]上海交通大学,电力传输与功率变换控制教育部重点实验室,上海200030

出　　处：《电力电子技术》2018年第12期69-72,共4页Power Electronics

基　　金：国家高技术研究发展计划(863)(2014AA052602).

摘　　要：三电平中点箝位型(NPC)逆变器存在中点电压偏移问题。基于虚拟空间矢量建立数学模型,消除传统空间矢量脉宽调制(SVPWM)算法的中矢量对中点电压的影响。引入中点电压调节系数,通过分配正负小矢量的作用时间实现中点电压的平衡控制。基于g,h坐标系,提出一种参考电压矢量所在区域的快速判定方法,计算简单,避免了传统直角坐标系所需的大量三角函数计算。采用基于虚拟空间矢量的最近三矢量(NTV)方法合成参考电压矢量,给出开关序列设计。仿真和实验结果证明该方法能够有效控制三电平NPC逆变器的中点电压。The problem of neutral-point voltage drift in three-level neutral point clamped(NPC) inverter cannot be solved by traditional modulation method.In order to solve this problem, virtual space vector pulse width modulation(SVPWM) is adopted.The adjustment coefficient of neutral-voltage balance is introduced and the neutral-point voltage is controlled by the action time of small vectors pairs.To avoid the problems of large computation of traditional rectangular coordinate algorithm,a new sector judging algorithm based on g,h coordinates is proposed.The reference vector is synthesized by using the nearest three vector(NTV) method based on virtual space vector and the switching sequence is determined.Simulation and experimental results are given to validate the method.

关 键 词：逆变器 中点箝位型 虚拟空间矢量 

分 类 号：TM464[电气工程—电器]