电子器件2018，Vol.41Issue(2)：307-312,6.DOI:10.3969/j.issn.1005-9490.2018.02.006
一种低漏电流七开关无变压器型光伏并网逆变器拓扑
A Low Leakage Current Seven-Switch Transformerless Photovoltaic Grid-Connected Inverter Topology
摘要
Abstract
The transformerless photovoltaic inverter systems should be disconnected from the grid within 0.3 s,in case,the leakage current is higher than 300 mA. In order to solve the leakage current caused by the common-mode voltage variation,a new seven-switches inverter topology(H7) is proposed. It uses two switches in the input DC side to ensure DC-AC decoupling during free wheeling period to keep the common-mode voltage in a constant status. Judging from the modulation mode,the inverter topology can also achieve double-frequency SPWM strategy to reduce current ripple wave. The heat balance is benefited with the switches working criss-crossed. Finally,a 2 kW prototype is built to verify peak value of leakage current suppressed is only 60 mA. Comparing with the traditional topology,capability of H7 is better. It provides an effective improvement in safe margin of systems.关键词
无变压器型逆变器/漏电流抑制/交直流解耦/共模电压/倍频SPWMKey words
transformerless inverter/leakage current suppressed/DC-AC decoupling/the common-mode voltage/double-frequency SPWM分类
信息技术与安全科学引用本文复制引用
廖志凌,丁蔓菁,刘康,吴超,姜宇珺,张凯..一种低漏电流七开关无变压器型光伏并网逆变器拓扑[J].电子器件,2018,41(2):307-312,6.基金项目
中国博士后基金项目(2012M521009) （2012M521009）
江苏高校优势学科建设工程项目(PAPD) （PAPD）
