Abstract: In order to achieve improved single-phase operation of an inverter having a first input pole and a second input pole and including at least three phase branches, each having at least one upper power switch and at least one lower power switch connected in series to the at least one upper power switch via an output pole a switching unit is provided. The switching unit is designed to switch the inverter from multi-phase operation to single-phase operation by closing a center point connection switch in order to connect the third output pole to the DC link center point. The switching unit is further designed, in single-phase operation, to effect a control of the upper and lower power switch of the third phase branch for symmetrizing the DC link voltages at the first and second DC link capacitors.

Abstract: A method for operating an inverter (1) of a photovoltaic installation is specified, wherein a reference value/reference profile of at least one parameter of the photovoltaic installation is compared with an actual value/actual profile of said parameter. If the deviation between said actual value/actual profile and the reference value/reference profile exceeds a predefinable threshold, then the inverter function of the inverter (1) is at least temporarily disabled. Furthermore, an inverter (1) for carrying out said method is specified.