| Abstract |
The market of PV systems is rapidly expanding during the last years and the transformerless DC/AC inverters are key components in this evolution. Despite its design and control simplicity, atransformerless full-bridge DC/AC inverter may exhibit a high leakage ground current, due tocapacitive coupling between the solar panels and ground, which prohibits its employment insingle-phase PV systems. Thus, multiple alternative transformerless PV inverter topologies have beendeveloped in the past, which, however, comprise additional power devices and/or passive components.In this paper, a new modulation method is proposed for optimally controlling the power switches oftransformerless single-phase full-bridge PV inverters, such that their leakage ground current isminimized. The design results demonstrate that by using the proposed technique, the leakage groundcurrent of transformerless full-bridge inverters is reduced below the maximum limit imposed by theVDE 0126-1-1 standard, thus enabling their application in single-phase PV installations, instead ofmore complex PV inverter structures. |
