Design and Development of Common Group Based Single Stage Boost Inverter Topologies for Photo Voltaic Applications

Abstract

Among all renewable energy sources, photovoltaic (PV) energy is the superior newlinechoice for residential and commercial distribution systems. PV energy accounts for newlinemore than 50 percent of new renewable energy capacity additions annually and plays newlinea pivotal role in the growth of renewables. However, the output voltage of PV energy newlinesystems is limited, and utilizing a voltage source inverter (VSI) leads to the step down newlinefor the DC-AC power conversion. Hence, it is necessary to boost the PV voltage before newlineconnecting to the grid. Generally, a DC-DC power converter or a line frequency transformer newlineis used in cascade with the VSI to supply power at the rated voltage to the load or newlinegrid. However, using more power conversion stages degrades the system s performance. newlineSimilarly, employing a line-frequency transformer increases the size of the system. newlineTo address these limitations, impedance source networks are explored, which newlineoffer several advantages, including a wide range of power conversion types (AC-DC, newlineDC-DC, DC-AC), the capability to buck-boost the input voltage, and the ability to newlineachieve single-stage power conversion. Additionally, it utilizes the shoot-through (ST) newlinestate, making it a viable alternative to conventional two-stage power conversion methods. newlineHowever, most impedance source inverters (ISI) require more than four controlled newlineactive switches and two intermediate impedance elements. Furthermore, due to the newlineabsence of galvanic isolation in ISI (ZSI, Q-ZSI, SBI, etc.) topologies, the switching newlinenature of the inverter establishes a high-frequency common mode voltage (CMV) across newlinethe parasitic capacitance (CPV ) of the PV panel. The CMV excites the resonant circuit newlineformed between the parasitic capacitance and the output filter inductor, resulting in the newlinegeneration of a leakage current that flows through the ISI. Consequently, there may be newlineharmonics injected into the grid, which leads to a reduction in the life span of solar PV newlinesystems and a deterioration of electromagnetic compatibility (EMC). Additionally