Research on Leakage Current Suppression of Novel Three-Phase Three-Level Non-Isolated PV Inverter
Guo Xiaoqiang, Zhu Tieying
Key Laboratory of Power Electronics for Energy Conservation and Drive Control of Hebei Province School of Electrical Engineering Yanshan University Qinhuangdao 066004 China
Abstract A novel three-phase three-level non-isolated PV inverter is proposed in this paper based on the neutral-point-clamped (NPC) inverter. The characteristics of working states and leakage current were studied. Different from the NPC inverter, the topology of proposed inverter is so brief and it only consists of twelve switches and two DC capacitors without extra devices, such as six clamped diodes for the NPC. In order to suppress the leakage current, the relationship between the switch states and the common-mode voltage was analyzed and a novel Single-Carrier modulation was proposed based on the traditional modulation for two-level inverters. Finally, in order to verify the effectiveness of the proposed circuit and modulation strategy, the simulations and the experiments connected to the grid, inductance experiments were conducted. The results of the simulations and experiments confirm that the proposed topology is feasibility and the modulation is effective.
Guo Xiaoqiang,Zhu Tieying. Research on Leakage Current Suppression of Novel Three-Phase Three-Level Non-Isolated PV Inverter[J]. Transactions of China Electrotechnical Society, 2018, 33(1): 26-37.
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2018, Vol. 33 
