A New Six-Level Transformer-Less Grid-Connected Solar Photovoltaic Inverter With Less Leakage Current

• Published in: IEEE access Vol. 10; pp. 63736 - 63753
• Main Authors: Kurdkandi, Naser Vosoughi, Marangalu, Milad Ghavipanjeh, Mohammadsalehian, Shamim, Tarzamni, Hadi, Siwakoti, Yam P., Islam, Md. Rabiul, Muttaqi, Kashem M.
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Capacitors; Converters; Electric potential; Harmonic distortion; Inverters; Leakage current; leakage current limitation; Leakage currents; photovoltaic application; Photovoltaic cells; Reactive power; Switches; Topology; Transformer-less inverter; Transformers; Voltage; voltage boosting ability
• ISSN: 2169-3536; 2169-3536
• DOI: 10.1109/ACCESS.2022.3182240

This paper presents a novel structure of the transformer-less grid-connected inverters. The proposed inverter is combined with six power switches and two power diodes which can generate six voltage levels at the output. Furthermore, the proposed inverter can overcome the leakage current issue in the photovoltaic (PV) system, which is the major problem in grid-tied PV applications. Additional significant features include- reduced filter size, lower total harmonic distortion (THD) of the injected current to the grid, and voltage boosting ability. Moreover, the proposed topology provides full reactive power support to the grid. A control strategy is designed and implemented to provide a voltage boost ability without using any additional dc-dc boost converter. Finally, the performance of the proposed inverter is validated by the 770 <inline-formula> <tex-math notation="LaTeX">W </tex-math></inline-formula> laboratory prototype.