Novel Common-Mode Current Suppression Method in Transformerless PV Grid-Connected System

作者：Liu, Dongliang; Zhu, Haoqi^*; Zhao, Ruiguang

来源：Applied Sciences-Basel, 2018, 8(11): 2072.

DOI：10.3390/app8112072

• Non-isolated
• PV grid-connected system
• common-mode current
• inner loop
• high-frequency component

The existence of high-frequency components in common-mode (CM) current would reduce the stability of a non-isolated PV grid-connected system. It has great impacts on the output power quality when the generated power from PV is low. The method of single CM inner loop in suppressing the high-frequency components has poor effect. Based on the CM equivalent circuit model and the cause analysis of the CM current, a novel dual CM inner loops method is proposed to restrain the high-frequency components in CM current. This method not only meets the grid connection demand of CM current, but also overcomes the high frequency resonant problem. Furthermore, the high-frequency components in CM current from the outer parasitic circuit are substantially reduced. Finally, the proposed method is verified by simulation and experimental results.

• 出版日期2018-11
• 单位杭州电子科技大学