摘要
为改善光伏并网逆变器的共模电压不恒定的问题,分析了全桥逆变器的共模等效电路,提出一种基于混合桥臂的中点钳位型光伏并网逆变器,通过连接于直流电容中点的2个二极管或2个开关管的钳位作用,使逆变器的共模电压在续流阶段保持恒定,并且与传统的具有中点钳位功能的H6电路相比,该结构具有更低的导通损耗和更为简单的控制方式.仿真和实验结果表明:改进的电路结构具有更低的共模漏电流和恒定的共模电压.
In order to improve the common-mode behavior of the photovoltaic grid connected inverter,this paper analyzes the equivalent common-mode circuit of the full bridge inverter.A kind of neutral-point-clamped photovoltaic grid connected inverter is proposed based on the combined bridges.The common-mode voltage is kept constant during the free wheeling period by two diodes or switches which are connected to the middle of the DC capacitance.Compared to the traditional H6 topologies with neutral-clamping circuits,the proposed inverter has less conduction loss and simpler controlling method.The simulation and experimental results demonstrate that the improved topology has lower leakage current and constant common-mode voltage.
出处
《北京交通大学学报》
CAS
CSCD
北大核心
2016年第3期19-24,共6页
JOURNAL OF BEIJING JIAOTONG UNIVERSITY
关键词
并网逆变器
共模电压
单极性调制
中点钳位型光伏并网逆变器
grid connected inverter
common-mode voltage
unipolar modulation
neutral-clamping photovoltaic inverter
