Abstract: A method operates a power converter having power converter arms, which are switchable between in each case an AC voltage side and a DC voltage side or connectable to phase lines of an AC voltage power supply system. Each power converter arm has a series circuit of switching modules each having a plurality of semiconductor switches and an energy store, in which at least one temperature value for the power converter is determined. A setpoint current limitation value is determined taking into consideration the temperature value, and a setpoint current value is determined taking into consideration the setpoint current limitation value. The temperature value, the arm setpoint current value, the arm actual current value and/or the arm setpoint current limitation value is time-integrated to form an arm integral value. When the arm integral value reaches or exceeds a predetermined arm integral threshold value, a protective measure is performed.

Abstract: A converter includes an AC side to be connected to an AC network at a connecting point, a grid following controller configured to control a steady state current at the connecting point, and a grid forming controller configured to actively control frequency and voltage at the connecting point. The grid following controller and the grid forming controller share an underlying current controller. A method for operating the converter is also provided.

Abstract: A method operates a power converter having at least one series circuit of switching modules, which each have semiconductor switches and an energy store. In which method a switching frequency of the switching modules is controlled by tolerance based modulation, and the forming of a switching integral value for the tolerance based modulation takes into account an absolute amount of an arm current flowing through the series circuit. A power converter has a control device that is configured to perform the method.

Abstract: A power converter has at least one series circuit of switching modules that each have semiconductor switches and an energy storage unit. A method of operating the power converter includes a step of making a prediction for at least one voltage value of the power converter and carrying out switching operations on the switching modules based on the prediction in order to regulate a switching frequency. There is also described a power converter that is configured to carry out a method according to the invention.

Abstract: A power converter arrangement with a modular multi-level converter which includes a series circuit of switch modules which each have a plurality of semiconductor switches and an energy source. Some of the switch modules are of a first type and others of the switch modules are of a second type. During operation, a positive switch module voltage, a negative voltage module voltage, or a null voltage is generated at connection terminals of the switch modules of the first type, and a positive switch module voltage or a null voltage can be generated at connection terminals of the switch modules of the second type. The power converter arrangement further contains a support structure having a number of levels, which each have receptacles in which the switch modules are arranged, with both switch modules of the first and second type being arranged in each level of the support structure.

Abstract: A method operates a power converter that contains power converter arms. Each of the power converter arms has switching modules and each of the switching modules has a plurality of semiconductor switches and an energy store. A temperature value for the power converter is ascertained on the basis of a state model of the power converter, wherein the ascertainment is repeated so as to obtain time-related temperature values. A number and a magnitude of temperature swings that have occurred are ascertained from the temperature values, and a remaining service life for the power converter is estimated based on the ascertained number and magnitude. A power converter is configured to carry out the above-described method.

Abstract: An assembly having a multilevel power converter, which has at least one phase module, wherein the phase module has a plurality of modules, each with a first electrical module terminal and a second electrical module terminal. The plurality of modules includes modules of a first type, which are able to output a voltage of only one polarity or zero voltage at their first electrical module terminal and their second electrical module terminal. The plurality of modules includes modules of a second type, which are able to output a voltage of one polarity, a voltage of opposite polarity or zero voltage at their first electrical module terminal and their second electrical module terminal. Depending on the polarity of a voltage across the modules of the second type, a voltage limiting device limits the voltage.

Abstract: A method operates a power converter having power converter arms, which are switchable between in each case an AC voltage side and a DC voltage side or connectable to phase lines of an AC voltage power supply system. Each power converter arm has a series circuit of switching modules each having a plurality of semiconductor switches and an energy store, in which at least one temperature value for the power converter is determined. A setpoint current limitation value is determined taking into consideration the temperature value, and a setpoint current value is determined taking into consideration the setpoint current limitation value. The temperature value, the arm setpoint current value, the arm actual current value and/or the arm setpoint current limitation value is time-integrated to form an arm integral value. When the arm integral value reaches or exceeds a predetermined arm integral threshold value, a protective measure is performed.

Abstract: A method controls a power converter in which a target value of a control parameter is limited by at least one limiting value. The method is characterized in that the at least one limiting value is determined dynamically over time as a function of a power converter temperature. A power converter system having a control device is provided and configured to carry out the method.

Abstract: The subject of the present invention is an arrangement for switching on a two-way switch of a converter module. A power generation device for providing electric power for switching on the two-way switch is provided that is suitable for converting electromagnetic radiation into electrical power. There is also described a converter module for a modular multi-level converter having the arrangement and a method for producing operational standby for a converter module having a two-way switch.

Abstract: A modular multilevel converter has a plurality of sub-modules, each of which includes at least two electronic switching elements and an electrical energy storage device. The sub-modules are controlled by a control device. An optical output of the control device of the converter is connected to an input of an optical distributor by way of a first optical waveguide. A plurality of outputs of the optical distributor are individually connected to an optical input of one of the sub-modules, respectively, by way of a second optical waveguide.

Abstract: A modular multilevel converter includes a plurality of sub-modules. Each of the sub modules has at least two electronic switching elements, an electrical energy storage device, two galvanic power terminals, an optical communication input (222) and an optical communication output. A plurality of the sub-modules is connected to a series circuit by way of their communication input and communication output.

Abstract: An arrangement includes at least one series circuit having at least two series-connected submodules and an inductor. At least one of the submodules in one or a plurality of the series circuits has a step-up/step-down converter and a storage module. A protective module with at least one actuator is electrically connected between the step-up/step-down converter and the storage module. A method for operating the arrangement is also provided.

Abstract: A modular multilevel converter has a plurality of sub-modules, each of which includes at least two electronic switching elements and an electrical energy storage device. The sub-modules are controlled by a control device. An optical output of the control device of the converter is connected to an input of an optical distributor by way of a first optical waveguide. A plurality of outputs of the optical distributor are individually connected to an optical input of one of the sub-modules, respectively, by way of a second optical waveguide.

Abstract: A sub-module of a modular braking unit that is connected to a DC transmission network. Each sub-module has an inverse diode, and a storage capacitor connected in parallel with the inverse diode via a free-wheeling diode. An energy-consuming switching unit is connected to the storage capacitor. In order to provide a sub-module of this type such that the braking unit can function with relatively low losses in the stand-by and idle state, the sub-module is provided with an actively switchable semiconductor bypass path in parallel with the inverse diode. A braking unit has a plurality of series-connected sub-modules and we disclose a method for operating a braking unit of this type.

Abstract: A modular multilevel converter includes a plurality of sub-modules. Each of the sub modules has at least two electronic switching elements, an electrical energy storage device, two galvanic power terminals, an optical communication input (222) and an optical communication output. A plurality of the sub-modules is connected to a series circuit by way of their communication input and communication output.

Abstract: The subject of the present invention is an arrangement for switching on a two-way switch of a converter module. A power generation device for providing electric power for switching on the two-way switch is provided that is suitable for converting electromagnetic radiation into electrical power. There is also described a converter module for a modular multi-level converter having the arrangement and a method for producing operational standby for a converter module having a two-way switch.

Abstract: An arrangement includes at least one series circuit having at least two series-connected submodules and an inductor. At least one of the submodules in one or a plurality of the series circuits has a step-up/step-down converter and a storage module. A protective module with at least one actuator is electrically connected between the step-up/step-down converter and the storage module. A method for operating the arrangement is also provided.

Abstract: A method and apparatus are provided for balancing currents of two or more parallel-connected power semiconductor switches during an on-state of the switches. A control terminal of each switch is driven by a driver unit. The method includes determining ratios between the currents through the switches. For each switch, the method includes controlling the voltage at the control terminal on the basis of the ratios by controlling a level of a supply voltage of the driver unit of the switch, and after a turn-on commutation transient, modulating the output of the driver unit. The duty cycle of the modulation is controlled to minimize the time required for the transition of the voltage at the control terminal from the one voltage level to another.

Abstract: A sub-module of a modular braking unit that is connected to a DC transmission network. Each sub-module has an inverse diode, and a storage capacitor connected in parallel with the inverse diode via a free-wheeling diode. An energy-consuming switching unit is connected to the storage capacitor. In order to provide a sub-module of this type such that the braking unit can function with relatively low losses in the stand-by and idle state, the sub-module is provided with an actively switchable semiconductor bypass path in parallel with the inverse diode. A braking unit has a plurality of series-connected sub-modules and we disclose a method for operating a braking unit of this type.