A Transformerless Single-Phase Current Source Inverter Topology and Control for Photovoltaic Applications

Energies

Nimrod Vazquez¹  Jorge Cardoso¹  Claudia Hernandez¹  Joaquin Vaquero² 

[1] Department of Electronics Engineering, National Technological of Mexico-Technological Institute of Celaya, Celaya 38010, Mexico;Electronic Technology Department, King Juan Carlos University, 28933 Mostoles, Madrid, Spain;

关键词: transformerless inverter;    leakage current;    current source inverter;    renewable sources;    grid-tied photovoltaic systems;   

DOI  :  10.3390/en11082011

来源: DOAJ

【 摘 要 】

Low power grid-tied photovoltaic (PV) generation systems increasingly use transformerless inverters. The elimination of the transformer allows smaller, lighter and cheaper systems, and improves the total efficiency. However, a leakage current may appear, flowing from the grid to the PV panels through the existing parasitic capacitance between them, since there is no galvanic isolation. As a result, electromagnetic interferences and security issues arise. This paper presents a novel transformerless single-phase Current Source Inverter (CSI) topology with a reduced inductor, compared to conventional CSIs. This topology directly connects the neutral line of the grid to the negative terminal of the PV system, referred as common mode configuration, eliminating this way, theoretically, the possibility of any leakage current through this terminal. The switches control is based on a hysteresis current controller together with a combinational logic circuitry and it is implemented in a digital platform based on National Instruments Technology. Results that validate the proposal, based on both simulations and tests of a low voltage low power prototype, are presented.

【 授权许可】

Unknown