Abstract: A three-phase inverter circuit includes an inverter incorporating a plurality of controllable power switches, and an electronic control device adapted to control the power switches. The control device in the event of a measured voltage drop on one phase is adapted to supply a reactive current on the phase with voltage drop and to supply and/or draw an active current on at least one phase without voltage drop.

Abstract: An uninterrupted power supply (UPS) circuit unit for uninterrupted power supply of consumers of a power generation plant for feeding current into a power network, including an inductance element, in particular a transformer and/or a choke, and a first UPS control circuit which is connected to the inductance element and comprises a DC power path which is connected to a DC power source, wherein the first UPS control circuit is adapted to guarantee uninterrupted power supply of the consumers from the DC power source via the DC power path in the event of a voltage drop in the power network, wherein the UPS circuit unit comprises at least one further independent UPS control circuit connected to the inductance element, arranged parallel to the first UPS control circuit and having a further DC power path which is connected to a DC power source.

Abstract: A three-phase inverter circuit includes an inverter comprising a plurality of controllable power switches, and an electronic control device adapted to control the power switches. The control device in the event of a measured voltage drop on one phase is adapted to supply a reactive current on the phase with voltage drop and to supply and/or draw an active current on at least one phase without voltage drop.