Abstract: A method controls a converter assembly which has a line-commutated converter. The line-commutated converter has an alternating voltage terminal which can be connected via a phase conductor to an alternating voltage network. The converter assembly further has a switch module branch which is arranged serially in the phase conductor and which contains a series circuit of switch modules at each of the terminals of which bipolar voltages can be generated which add up to a branch voltage. A connection voltage to a connection point between the switch module branch and the converter is controlled by adjusting an amplitude of a positive sequence component of the branch voltage. The converter assembly is configured to carry out a control method for controlling the converter assembly.

Abstract: A method of operating a thyristor-based line-commutated multi-phase power converter on a multi-phase AC voltage connection point, which is supplied by an AC voltage network. Between the AC voltage connection point and an AC voltage connection of the power converter, a series circuit of modules is arranged for each phase. Each of the series circuits has a first electronic switching element, a second electronic switching element, and an electric energy storage device. The voltages of the phases of the AC voltage connection point are measured and, if an undervoltage is detected on a phase of the AC voltage connection point, an additional voltage adding to the voltage of that phase is generated by way of the series circuit of modules allocated to that phase in such a way that the voltage of that phase is increased, at least temporarily.

Abstract: A converter arrangement has a line-commutated converter with an AC voltage terminal to be connected to an AC voltage grid via at least one phase line. The converter arrangement has at least one switching module branch that is arranged in series in the at least one phase line and that includes a series connection of switching modules at whose terminals bipolar voltages that sum to give a branch voltage are in each case able to be generated. A bypass branch is arranged in a parallel connection to the switching module branch. At least one switching device is arranged in the bypass branch. The switching device includes activatable semiconductor switches that are connected in antiparallel. There is also described a method for starting up the converter arrangement.

Abstract: A method controls a converter assembly which has a line-commutated converter. The line-commutated converter has an alternating voltage terminal which can be connected via a phase conductor to an alternating voltage network. The converter assembly further has a switch module branch which is arranged serially in the phase conductor and which contains a series circuit of switch modules at each of the terminals of which bipolar voltages can be generated which add up to a branch voltage. A connection voltage to a connection point between the switch module branch and the converter is controlled by adjusting an amplitude of a positive sequence component of the branch voltage. The converter assembly is configured to carry out a control method for controlling the converter assembly.

Abstract: A method of operating a multilevel converter having multiple phase modules, each with three phase module branches. In a first switching position, a switching device of each phase module connects an alternating voltage connection of the phase module to a first connection point between a first phase module branch and a third phase module branch. In a second switching position, the switching device connects the alternating voltage connection to a second connection point between the third phase module branch and a second phase module branch. In the method, circulating currents of the multilevel converter are controlled in accordance with total energy variables and differential energy variables of the phase modules to balance the energy between the phase module branches.

Abstract: A converter arrangement has a line-commutated converter with an AC voltage terminal to be connected to an AC voltage grid via at least one phase line. The converter arrangement has at least one switching module branch that is arranged in series in the at least one phase line and that includes a series connection of switching modules at whose terminals bipolar voltages that sum to give a branch voltage are in each case able to be generated. A bypass branch is arranged in a parallel connection to the switching module branch. At least one switching device is arranged in the bypass branch. The switching device includes activatable semiconductor switches that are connected in antiparallel. There is also described a method for starting up the converter arrangement.

Abstract: A multilevel power converter has at least one phase module with a plurality of modules connected between positive and negative DC voltage connections. The phase module has a first phase module branch connected to the positive DC voltage connection, and a second phase module branch connected to the negative DC voltage connection. Each of the modules has at least two electronic switching elements and an electric energy storage unit. A third phase module branch connects the first phase module branch to the second phase module branch. A switching device connects an AC voltage connection of the multilevel power converter to a first connection node between the first phase module branch and the third phase module branch in a first switch position and connects the AC voltage connection to a second connection node between the third phase module branch and the second phase module branch in a second switch position.

Abstract: A device for inverting an electric parameter in the field of power transmission and distribution has a converter that can be connected between an alternating current grid and a DC circuit and having power semiconductor valves extending between an alternating current connection and a DC voltage connection. Each power semiconductor valve has a series circuit of bipolar submodules, each with an energy storage device and a power semiconductor circuit in parallel with the energy storage device, and a grid connection unit connected to the alternating current connection for connecting to the alternating current grid. Simple, effective, and inexpensive symmetrization of the voltages in the DC voltage circuit relative to ground potential is brought about. A star point reactor is connected between the grid connection unit and the inverter with a potential node, including throttle coils connected to a grounded star point.

Abstract: The superconducting winding (2) is configured such that it has a band-shaped HTS conductor (4) of the Röbel-conductor type, made of band-shaped HTS individual conductors that are transposed among each other. An armoring band (5) is to be wound to the prefabricated HTS conductor (4), the band not being metallurgically connected to the HTS conductor (4) and being subject to a comparatively larger winding tension (WZ2). The armoring band (5) is wound at a winding tension (WZ2) that is at least 1.5 times, preferably at least 3 times as large as the winding tension (WZ1) of the HTS conductor (4).

Abstract: A device for inverting an electric parameter in the field of power transmission and distribution has a converter that can be connected between an alternating current grid and a DC circuit and having power semiconductor valves extending between an alternating current connection and a DC voltage connection. Each power semiconductor valve has a series circuit of bipolar submodules, each with an energy storage device and a power semiconductor circuit in parallel with the energy storage device, and a grid connection unit connected to the alternating current connection for connecting to the alternating current grid. Simple, effective, and inexpensive symmetrization of the voltages in the DC voltage circuit relative to ground potential is brought about. A star point reactor is connected between the grid connection unit and the inverter with a potential node, including throttle coils connected to a grounded star point.

Abstract: The superconducting winding (2) is configured such that it has a band-shaped HTS conductor (4) of the Röbel-conductor type, made of band-shaped HTS individual conductors that are transposed among each other. An armoring band (5) is to be wound to the prefabricated HTS conductor (4), the band not being metallurgically connected to the HTS conductor (4) and being subject to a comparatively larger winding tension (WZ2). The armoring band (5) is wound at a winding tension (WZ2) that is at least 1.5 times, preferably at least 3 times as large as the winding tension (WZ1) of the HTS conductor (4).