Buck Boost Transformer Less in PV System with Grid Connected

Abstract

For single-phase grid-connected solar PV applications, a novel single-stage buck boost trans formerless inverter (BBTI) topology is presented in this paper. Leakage currents are eliminated since the input PV source and grid neutral share a common ground in this topology. In addition, the buck-boost capability of the proposed topology ensures that the maximum power point is maintained throughout a wide range of input PV voltage variations. The fact that only one energy storage inductor is used in the proposed topology makes it symmetrical during both grid half cycles. Additionally, the proposed topology's two out of five switches operate at a line frequency, resulting in low switching losses, while the remaining three switches operate in any mode with low losses. To control the proposed inverter topology, a straightforward sine-triangle pulse width modulation strategy is outlined and analyzed across all operating modes. The 300W laboratory prototype is the subject of experiments, and all of the major findings are presented in the paper. These findings demonstrate that the proposed system offers higher efficiency with lower THD in output current.