Cascaded photovoltaic grid-connected inverter, control method and control device for the same

摘要

Provided are a cascaded photovoltaic grid-connected inverter, a control method and a control device for the same. The method includes: determining whether at least one of inverter units of the cascaded photovoltaic grid-connected inverter is over-modulated; injecting a reactive current to a power grid to make a grid-connected current effective value greater than or equal to √{square root over (2)}*i