A single-phase asymmetric full-bridge non-isolated photovoltaic grid-connected inverter consists of an input capacitor branch (1), an improved full-bridge switch unit (2) and a grid-connected filter branch (3). The inverter adds an auxiliary switch on the basis of a full-bridge circuit to realize disengaging of a follow current loop at a follow current stage from an output of a photovoltaic battery, and the potential of the follow current loop is half or about half of the battery voltage, thus suppressing and eliminating the leak current of a non-isolated photovoltaic grid-connected inverter. As compared to the existing non-isolated photovoltaic grid-connected inverter topology, it has the following advantages: the number of switch tubes of the current flow passage is reduced, thus reducing on-state loss and improving the conversion efficiency; and it is suitable for a photovoltaic grid connection scenario without inverter isolation.
展开▼
