Abstract: A method for operating an inverter, the DC voltage input of which is connected to a positive pole (PV+) and to a negative pole (PV?) of a PV generator and the AC voltage output of which is connected to an AC grid via a transformer, is disclosed. The method includes determining a potential of the positive pole and/or the negative pole (UPV+, UPV?) of the PV generator with respect to a ground potential by a monitoring circuit, and selecting a modulation method for controlling power switches of the inverter from a number of modulation methods stored in a storage device of the inverter based on the determined potential (UPV+, UPV?) such that a voltage stress on components of the PV system arranged on the AC side, with respect to ground, is reduced. The method further includes using the selected modulation method to control the power switches for the purpose of converting a DC input voltage into an AC output voltage.

Abstract: A method for operating an inverter, the DC voltage input of which is connected to a positive pole (PV+) and to a negative pole (PV?) of a PV generator and the AC voltage output of which is connected to an AC grid via a transformer, is disclosed. The method includes determining a potential of the positive pole and/or the negative pole (UPV+, UPV?) of the PV generator with respect to a ground potential by a monitoring circuit, and selecting a modulation method for controlling power switches of the inverter from a number of modulation methods stored in a storage device of the inverter based on the determined potential (UPV+, UPV?) such that a voltage stress on components of the PV system arranged on the AC side, with respect to ground, is reduced. The method further includes using the selected modulation method to control the power switches for the purpose of converting a DC input voltage into an AC output voltage.

Abstract: A grid-connected inverter for feeding current via a transformer into an electric power grid includes an output bridge arrangement that is actuated via a pulse width modulator, wherein a periodic auxiliary signal is used to determine switching times of the output bridge arrangement. The inverter also includes a synchronization unit for phase synchronization of the auxiliary signal with the electric power grid, wherein the synchronization unit is configured to set a predetermined phase offset (??0) of the periodic auxiliary signal with respect to a phase of the electric power grid.

Abstract: A grid-connected inverter for feeding current via a transformer into an electric power grid includes an output bridge arrangement that is actuated via a pulse width modulator, wherein a periodic auxiliary signal is used to determine switching times of the output bridge arrangement. The inverter also includes a synchronization unit for phase synchronization of the auxiliary signal with the electric power grid, wherein the synchronization unit is configured to set a predetermined phase offset (??0) of the periodic auxiliary signal with respect to a phase of the electric power grid.