The role of diodes in the leakage current suppression mechanism of decoupling transformerless PV inverter topologiesThe role of diodes in the leakage current suppression mechanism of decoupling transformerless PV inverter topologies Δημοσίευση σε Συνέδριο Conference Publication 2023-05-242021enThis work was performed within the framework of the project “eSOLAR: Principle and control of high-efficiency Buck-Boost type Photovoltaic inverter” of the program “Bilateral and Multilateral Research & Technology Co-operation between Greece and China”, funded by the Operational Program “Competitiveness, Entrepreneurship and Innovation 2014-2020” (co-funded by the European Regional Development Fund) and managed by the General Secretariat of Research and Technology, Ministry of Education, Research, and Religious Affairs under the project eSOLAR/T7ΔKI-00066.Conventional DC/AC inverters used for the integration of photovoltaic (PV) energy sources to the utility grid are known to give rise to ground leakage currents, which can damage the PV cells and cause safety hazards. A modern solution to the leakage current problem is offered by transformerless PV inverter topologies. This paper focuses on the class of decoupling transformerless topologies and provides a complete explanation of their leakage current suppression mechanism, by considering the commonly neglected role of the inverter diodes. It is demonstrated that, apart from additional semiconductor switches, the diodes are essential for achieving leakage current suppression, while the leakage current that flows through them radically affects the waveform of the inverter common-mode voltage. The presented analysis is supported by simulation results in MATLAB-Simulink.http://creativecommons.org/licenses/by/4.0/2021 10th International Conference on Modern Circuits and Systems Technologies Orfanoudakis, Georgios I Koutroulis Eftychios Κουτρουλης Ευτυχιος Foteinopoulos Georgios Φωτεινοπουλος Γεωργιος Institute of Electrical and Electronics Engineers Photovoltaics DC/AC inverter Transformerless Common-mode leakage current Decoupling H5 HERIC