Abstract: A method for ancillary supply in a modular multi-level converter with a plurality of modules arranged in strands, a respective module including at least two half bridges with semiconductor switches and at least one energy accumulator, which are interconnected in parallel. In the respective module, an at least single-core input terminal is formed through respective center tapping in at least one half bridge on an input side, and an at least single-core output terminal is formed through respective center tapping in at least one half bridge on an output side. The strands are interconnected into at least one star point on the at least single-core input terminal of a first module in the respective strand. A respective phase of a supply voltage in a high-voltage system is formed on the at least single-core output terminal of a last module in the respective strand.

Abstract: A method for a safety concept for an AC battery, in which the AC battery includes a central controller, a plurality of battery modules which respectively have a power board with a plurality of switching states, a plurality of contactors, a plurality of current sensors, a fault loop and a high-speed bus and is connected to a traction machine. The central controller has a hardware-programmable processor unit with at least one microprocessor core on which a control program is configured to control the battery modules, the plurality of contactors and the fault loop. A state machine is implemented by the control program. The battery modules are connected, starting from the central controller, via the high-speed bus and the fault loop. If an abort fault occurs, the AC battery is changed to a safe operating state. The safe state is achieved at least by emergency disconnection of the central controller.

Abstract: A measurement apparatus has a current sensor and at least one A/D converter, which current sensor has at least two channels (CH1, CH2), via which channels (CH1, CH2) the current sensor (30) respectively provides a measurement signal (CH1_SIG, CH2_SIG) characterizing the current. The at least two channels (CH1, CH2) include a first channel (CH1) and a second channel (CH2), which second channel (CH2) is designed to measure a greater maximum current than the first channel (CH1). Also described is a method for measuring a current flowing through a conductor by way of the measurement apparatus.

Abstract: A measurement apparatus has a current sensor and at least one A/D converter, which current sensor has at least two channels (CH1, CH2), via which channels (CH1, CH2) the current sensor (30) respectively provides a measurement signal (CH1_SIG, CH2_SIG) characterizing the current. The at least two channels (CH1, CH2) include a first channel (CH1) and a second channel (CH2), which second channel (CH2) is designed to measure a greater maximum current than the first channel (CH1). Also described is a method for measuring a current flowing through a conductor by way of the measurement apparatus.

Abstract: A method for a safety concept for an AC battery, in which the AC battery includes a central controller, a plurality of battery modules which respectively have a power board with a plurality of switching states, a plurality of contactors, a plurality of current sensors, a fault loop and a high-speed bus and is connected to a traction machine. The central controller has a hardware-programmable processor unit with at least one microprocessor core on which a control program is configured to control the battery modules, the plurality of contactors and the fault loop. A state machine is implemented by the control program. The battery modules are connected, starting from the central controller, via the high-speed bus and the fault loop. If an abort fault occurs, the AC battery is changed to a safe operating state. The safe state is achieved at least by emergency disconnection of the central controller.

Abstract: A battery system having a battery having at least one first battery element, at least one second battery element and a center tap between the at least one first and the at least one second battery element, a power changeover switch having a plurality of switching elements for changing over between the at least one first battery element and the at least one second battery element, and at least one pair of output terminals that is electrically connected to the battery, wherein the center tap has a first capacitive store arranged on it that has a store voltage that appears over an appropriate period in accordance with a first and/or second battery element voltage provided by the first and/or second battery element, wherein during the period in which the store voltage appears, a store current decreases from a maximum value to a value of zero.

Abstract: A battery system having a battery having at least one first battery element, at least one second battery element and a center tap between the at least one first and the at least one second battery element, a power changeover switch having a plurality of switching elements for changing over between the at least one first battery element and the at least one second battery element, and at least one pair of output terminals that is electrically connected to the battery, wherein the center tap has a first capacitive store arranged on it that has a store voltage that appears over an appropriate period in accordance with a first and/or second battery element voltage provided by the first and/or second battery element, wherein during the period in which the store voltage appears, a store current decreases from a maximum value to a value of zero.