带中心抽头电感的无直通单相三电平逆变器拓扑与控制策略  

Topology and Control Strategy of Anti Direct Connection Single-Phase Three-Level Inverter With a Center-Tapped Inductor

作　　者：瓦明达 李章勇 王晓兴 郑昕昕 WA Mingda;LI Zhangyong;WANG Xiaoxing;ZHENG Xinxin(CHN Energy Guangdong Integrated Energy Co.,Ltd.,Guangzhou 510799,Guangdong,China;Hefei University of Technology,Hefei 230009,Anhui,China)

机构地区：[1]国能(广东)能源发展有限公司,广东广州510799 [2]合肥工业大学,安徽合肥230009

出　　处：《电力大数据》2024年第10期74-82,共9页Power Systems and Big Data

基　　金：贵州电网管理创新项目(060000KM23010004)。

摘　　要：三电平逆变器具有功率器件电压应力小、桥臂输出电压谐波含量低等优势,在高压场合得到了广泛的应用。但为了避免直流侧的直通问题,需要在驱动信号中加入死区时间,这不仅会引入额外的低频谐波,还会加剧直流侧电容的不平衡程度,影响逆变器工作的可靠性。本文提出了一种带中心抽头电感的三电平逆变器,电感同时起到了防直通和滤波的作用,从拓扑结构本身避免了直流电容的直通,同时构建了电感的续流通路,避免了电感电流的突变;针对所提出的无直通逆变器拓扑,研究相应的三电平调制策略,并分析其与传统三电平拓扑的一致性。在此基础上,通过带中心抽头电感的等效,讨论了电感的滤波和防直通效果,以及实现电容均衡的拓扑优势,最后通过仿真和实验验证了理论分析的正确性。Three-level inverters have the advantages of low voltage stress in power devices and low harmonic content in bridge leg output voltage.They are widely used in high-pressure applications.In order to avoid the problem of direct connection on the DC side,dead-time is necessary to add in the drive signals of the power switches.Dead-time not only introduces additional low-frequency harmonics,but also exacerbates the imbalance of DC side capacitors.The reliability of inverter operation will be affected.This paper proposes a three-level inverter with a center-tapped inductor.The inductor serves both anti direct connection and filtering purposes.Thus the inverter can avoid direct connection problem from the topology.Also the inverter constructs a freewheeling path to avoid sudden changes of the inductor current.The corresponding three-level modulation strategy of the proposed inverter is studied.The consistency between the proposed inverter and traditional three-level inverter is analyzed.On the basis,the filtering and anti direct connection effects are discussed through the equivalence of the center-tapped inductor.The topological advantages of achieving capacitor balance is analyzed.Finally,the correctness of the theoretical analysis was verified through simulation and experiments.

关 键 词：无直通逆变器 死区 电容均衡 带中心抽头电感 三电平调制 

分 类 号：TM464[电气工程—电器]