Transformerless Inverter with Dynamic Voltage Boost and Zero leakage Current for PV System

Transformerless inverters (TIs) are highly efficient and have a high power density, making them a popular choice for grid-connected solar PV applications. This paper introduces a novel common-ground transformerless step-up 5level inverter design utilizing a single DC voltage source devoid of leakage current suitable for grid-connected PV applications. The proposed inverter is based on a hybrid switched capacitor (SC) concept, which uses integration of the boost inductor to facilitate continuous input current and dynamic voltage gain. The proposed circuit comprises eight switches and two SCs powered by a single input DC source. The primary advantages of the proposed single-stage topology encompass its commonground nature, boosting capability, reduced component count, lower cost, and smaller size compared to recently developed five-level topologies. However, these inverters commonly encounter issues with leakage current, which can lead to power losses and safety concerns. The proposed inverter design addresses this concern effectively. The configuration of the proposed inverter demonstrates a shared ground connection between the input and output terminals, ensuring a constant total common mode voltage (CMV). A thorough mathematical analysis of the proposed inverter was conducted, accompanied by the MATLAB/Simulink simulation results presentation. The simulation outcomes highlight the inverter's ability to boost output voltage, eliminate leakage current, and maintain suitable total harmonic distortion levels in output voltage and current waveforms.