山东电力技术2023，Vol.50Issue(12)：34-44,11.DOI:10.20097/j.cnki.issn1007-9904.2023.12.005
NPC/H桥逆变器调制策略及其中点电位控制
Modulation Strategy and Neutral-point Potential Control Method of NPC/H Bridge Inverter
摘要
Abstract
In view of the problems of the tedious algorithm and the DC-side capacitor voltage fluctuation in traditional modulation of the neutral-point clamped H(NPC/H)bridge inverter,working principles of the NPC/H bridge five-level inverter was analyzed,and a three-segment space vector pulse width modulation(SVPWM)algorithm using g-h coordinate system was proposed,which could simplify SVPWM algorithm and reduce the inverter output distortion under low switching frequency.The algorithm has the advantages of flexible option of switching state,lower switching loss and better harmonic performance.Based on the SVPWM algorithm,the causes of the DC-side capacitor voltage fluctuation were analyzed.According to the current direction and capacitor voltage difference,the neutral-point potential can abtain balance by selecting the left and right bridges′ switching states.The simulation model was established by using Simulink,and the output characteristics of the inverter under different switching frequency and modulation degrees were compared.Thus,the results verified the significant advantages of the three-segment switch sequence under low switching frequency conditions.Based on the NPC/H-bridge five-level inverter experimental platform with digital singnal processor and field-programmable gate array(DSP&FPGA)as the controller,the validity of the proposed modulation strategy and neutral-point potential control method were verified.关键词
NPC/H桥逆变器/空间矢量脉宽调制/中点电位控制Key words
NPC/H bridge inverter/SVPWM/neutral-point potential control分类
动力与电气工程引用本文复制引用
朱玉振..NPC/H桥逆变器调制策略及其中点电位控制[J].山东电力技术,2023,50(12):34-44,11.基金项目
国网山东省电力公司科技项目(520614220004).Science and Technology Project of State Grid Shandong Electric Power Company(520614220004). （520614220004）
