Abstract: The application describes a transfer circuit or system with a first DC bus for connecting a plurality of battery racks to an inverter bridge for a first power exchange with an AC grid. The transfer circuit or system has a second DC bus which is connected to the first DC bus via a DC/DC converter. The transfer circuit or system is arranged to disconnect at least one battery rack of the plurality of battery racks from the first DC bus and to connect it to the second DC bus for performing an intra-battery equalization process. The application also describes a system with a transfer unit and a method for performing an intra-battery equalization process.

Abstract: A power converter with an inverter that is configured to transform electrical power between a DC-side of the power converter and an AC-side of the power converter, includes a first port operatively connected to an AC-grid, a second port operatively connected to an AC-load, a third port connected to an external power source, and a fourth port operatively connected to a rechargeable DC-power storage. The power converter includes a DC/DC-converter between the third port and the inverter, to transfer electrical power provided by the external power source from the third port to the inverter. The inverter is configured to be grid forming and provide electrical power to the second port upon a power supply outage at the first port, the power converter includes a control unit to monitor the third port and detect parameters of the electrical power provided via the third port.

Abstract: Disclosed is an electrical unit with a first port configured to be operatively connected to an AC-grid, a second port configured to be operatively connected to an AC-load, and a third port to be operatively connected to an AC-side of a first inverter. The electrical unit includes a first choke arranged between the third port and the second port. The electrical unit is configured to transfer electrical power provided by the first inverter from the third port via the first choke to the second port. The electrical unit is configured to provide grid-forming electrical power to the second port in case of disconnection from the AC-grid at the first port. Further disclosed is a backup power system and a method for operating a backup power system.

Abstract: Disclosed is an electrical unit with a first port configured to be operatively connected to an AC-grid, a second port configured to be operatively connected to an AC-load, and a third port to be operatively connected to an AC-side of a first inverter. The electrical unit includes a first choke arranged between the third port and the second port. The electrical unit is configured to transfer electrical power provided by the first inverter from the third port via the first choke to the second port. The electrical unit is configured to provide grid-forming electrical power to the second port in case of disconnection from the AC-grid at the first port. Further disclosed is a backup power system and a method for operating a backup power system.

Abstract: A power converter with an inverter that is configured to transform electrical power between a DC-side of the power converter and an AC-side of the power converter, includes a first port and a second port arranged on the AC-side and a third port and a fourth port arranged on the DC-side of the power converter. The first port is configured to be operatively connected to an AC-grid, the second port is configured to be operatively connected to an AC-load, the third port is configured to be operatively connected to an external power source, and the fourth port is configured to be operatively connected to a rechargeable DC-power storage. The power converter includes a DC/DC-converter arranged between the third port and the inverter, which is configured to transfer electrical power provided by the external power source from the third port to the inverter.

Abstract: The disclosure relates to a method for operating a bidirectional battery converter connected to an AC grid, taking into account the availability of locally generated electrical power. Furthermore, the present disclosure relates to a battery converter comprising measuring devices for detecting the state of charge of a connected battery and comprising a controller, which performs the method.

Abstract: An inverter apparatus includes an input stage receiving DC electric power from a DC power generator for loading a DC voltage link, a DC/AC converter connected to the DC voltage link and feeding AC electric power into a power grid. The apparatus further includes a bidirectional connection for loading a battery out of the DC voltage link and for loading the DC voltage link out of the battery, and a controller operating the DC/AC converter and the bidirectional connection. The controller receives present values of relevant parameters of the battery including working data at least related to a state of charge and safety data indicating a safety state of the battery from a battery monitoring unit. The controller, in operating the bidirectional connection, considers the working data and is commanded by the safety data.

Abstract: The disclosure relates to a method for operating a bidirectional battery converter connected to an AC grid, taking into account the availability of locally generated electrical power. Furthermore, the present disclosure relates to a battery converter comprising measuring devices for detecting the state of charge of a connected battery and comprising a controller, which performs the method.

Abstract: An inverter apparatus includes an input stage receiving DC electric power from a DC power generator for loading a DC voltage link, a DC/AC converter connected to the DC voltage link and feeding AC electric power into a power grid. The apparatus further includes a bidirectional connection for loading a battery out of the DC voltage link and for loading the DC voltage link out of the battery, and a controller operating the DC/AC converter and the bidirectional connection. The controller receives present values of relevant parameters of the battery including working data at least related to a state of charge and safety data indicating a safety state of the battery from a battery monitoring unit. The controller, in operating the bidirectional connection, considers the working data and is commanded by the safety data.