A new transformer-less common grounded five-level grid-tied inverter with leakage current elimination and voltage boosting capability for photovoltaic applications

Due to serious Concerns such as air pollution, global warming, and fossil fuels shortcoming, renewable energy sources such as photovoltaic applications are dramatically being integrated into the power generation systems all of the world. Here, a new switched-capacitor-based transformer-less grid-tied inverter has been proposed. By applying the series-parallel switching technique of the utilized switched-capacitor module, the voltage boosting capability has been obtained. By implementing common ground technique, high overall efficiency and leakage current elimination capability have been obtained. Since the proposed inverter provides a multi-level output voltage, the total harmonic distortion of the injected grid current is reduced. The introduced control strategy has been implemented to control both active and reactive powers and generate the switches pulses. Therefore, a high quality and adjusted current is injected to the grid. This inverter requires a single renewable energy source as input DC source. Here, the comprehensive description of the proposed inverter and its performance with design considerations have been presented. The proposed structure has been compared with several similar structures and the obtained results have been investigated. To evaluate the performance of the proposed inverter, a 620 W laboratory prototype is assembled and experimental results are analyzed.

Automated summary

Due to concerns about air pollution, global warming, and the limitations of fossil fuels, renewable energy sources such as photovoltaic applications are being widely integrated into power generation systems worldwide. This study proposes a new switched-capacitor-based transformer-less grid-tied inverter, which utilizes a series-parallel switching technique to achieve voltage boosting capability and implements a common ground technique for high overall efficiency and leakage current elimination. The inverter provides multi-level output voltage, reducing total harmonic distortion of the injected grid current, and incorporates a control strategy for controlling both active and reactive powers. A laboratory prototype of the proposed inverter is assembled and experimental results are analyzed to evaluate its performance.