Method for minimizing network feedback of photovoltaic power plant, inverter and photovoltaic power plant

摘要

A method and associated system for minimizing grid feedback of a PV park to an energy supply grid connected to a point of common coupling is disclosed, wherein the PV park has a plurality of inverters divided into groups. The method includes, for at least a first inverter of each group, determining a first parameter representative of a first coupling impedance between the first inverter and the point of common coupling and determining a second parameter representative of a second coupling impedance between the group containing the first inverter and the point of common coupling. The method further includes storing the first parameter and the second parameter in an operating control unit of the first inverter, and, in daytime operation of the PV park, feeding in reactive power by the first inverter depending on the first parameter, said reactive power corresponding to the magnitude of a reactive power drawn by the respective underlying first coupling impedance. The method also includes, in night-time operation, deactivating all the inverters of a group with the exception of the first inverter and feeding in reactive power by the first inverter depending on the second parameter, wherein the reactive power fed in corresponds to a magnitude of a reactive power drawn by the respective underlying second coupling impedance.