非隔离型单相级联双降压式光伏并网逆变器及其漏电流分析  

TRANSFORMERLESS SINGLE-PHASE CASCADED DUAL-BUCK PHOTOVOLTAIC GRID-CONNECTED INVERTER AND ITS LEAKAGE CURRENT ANALYSIS

作　　者：熊振中 庄圣贤[1] 代云中[1] 黎国扬 唐炜祺 Xiong Zhenzhong;Zhuang Shengxian;Dai Yunzhong;Li Guoyang;Tang Weiqi(School of Electrical Engineering,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学电气工程学院,成都611756

出　　处：《太阳能学报》2021年第4期215-222,共8页Acta Energiae Solaris Sinica

基　　金：国家重点研发计划(2017YFB1200703)。

摘　　要：针对无隔离光伏并网逆变器中因高频共模电压产生的高频漏电流问题,提出一种非隔离型单相级联双降压式光伏并网逆变器及其调制策略。在逆变器光伏组件连接端加入2个开关管,实现了续流阶段与光伏组件的隔离;双降压式和独立续流二极管的结构可避免桥臂直通和降低导通损耗。接着对提出的调制策略分析电路工作特性,建立其在正负半周不同的共模等效模型,分析其漏电流抑制能力。最后搭建Matlab/Simulink仿真和DSP实验平台,仿真与实验结果验证了所提电路抑制漏电流的能力。Aiming at the high-frequency leakage current generated by high-frequency common-mode voltage in transformerless PV gridconnected inverter,a transformerless single-phase cascaded dual-buck photovoltaic grid-connected inverter is proposed.Its modulation strategy also is given out.Two switch tubes are added to the connection end of the inverter and the photovoltaic panel.This structure realized the isolation between the grid and the photovoltaic panels during the freewheeling stage.The structure of dual-buck and independent diodes can avoid shoot-through and reduce conduction losses.Then,the proposed modulation strategy is used to analyze the working characteristics of the circuit,and the common mode equivalent model of the circuit in the positive and negative half cycles is established,and the leakage current suppression capability is analyzed.Finally,the MATLAB/Simulink simulation and DSP experimental platform are built.The simulation and experimental results verify the ability of the proposed circuit to suppress leakage current.

关 键 词：逆变器 漏电流 光伏组件 调制策略 共模等效模型 

分 类 号：TM464[电气工程—电器]