Research on the Suppression Strategy of Photovoltaic Leakage Current Collection in the Whole County

Due to the parasitic capacitance between the photovoltaic system and the ground, a common-mode voltage will be generated in the inverter circuit, which will cause a leakage current in the circuit. If the leakage current is too large, it will cause many hazards, including the impact on the power grid and the substation. Therefore, how to reduce the leakage current correctly and reasonably is what we urgently need to study. Most of the previous research and literature on leakage current in photovoltaic systems focused on the research of a single photovoltaic inverter. The research on the leakage current of transformers often lacks practicability, and there are problems that do not conform to the actual situation. Therefore, this paper mainly studies the leakage current in the concentrated photovoltaic system, and considers the impact of the leakage current collected in the entire county. At the same time, this paper not only considers the collection of leakage current in the whole county, but also considers how to reasonably reduce the leakage current value, how to reduce the negative impact caused by leakage current, etc., which is of great practical significance. In this paper, the HERIC inverter circuit is mainly used for simulation experiments, considering the influence of line impedance, inverter switching frequency, inverter rated power and other factors on the collective leakage current in the entire county, and the parameters related to the influence of the collective leakage current are obtained. in conclusion. The most appropriate optimization is carried out on the original whole county photovoltaic, and the simulation experiment is carried out on the concentrated photovoltaic system, and the final collected leakage current value is compared with that before optimization to check whether it meets the optimization requirements.