摘要
共模电流问题是非隔离光伏并网系统需要解决的关键问题之一.VDE-0126-1-1标准规定,当漏电流超过规定值时,并网系统必须在规定时间内停止工作.针对共模电流问题,分析其产生的原因,研究和对比了了几种不同的调制方式,并详细分析了几种能够有效抑制或消除共模电流的电路拓扑结构,得到了不同拓扑结构之间抑制共模电流的共同特征.在此基础上,根据oHeric拓扑结构,提出了其相应的调制策略并分析和阐述了其工作原理.最后通过仿真验证了oHeric拓扑抑制共模电流的有效性.
Common mode current suppression is one of the key points for non-isolated photovoltaic grid system. In VDE-0126-1-1 specification, the photovoltaic systems should be disconnected from the grid within the stipulation time in case the leakage current exceeds specified value. In view of the problem of leakage current, the reason was analyzed firstly, researching and comparing different kinds of the modulation, some topologies which can restrain common mode current effectively were analyzed in details, and obtained the common feature about the different topologies. Based on the common feature, put forward the modulation strategy about oHeric topology, and analyze and elaborate the working principle. Finally, the simulation results show that the oHeric topology can effectively suppress common mode currents.
出处
《浙江工业大学学报》
CAS
北大核心
2015年第6期655-659,共5页
Journal of Zhejiang University of Technology
关键词
非隔离
共模电流
oHeric拓扑
调制策略
non-isolated
common mode current
oHeric topology
modulation strategy
