Abstract: An arrangement for connecting and disconnecting DC networks includes a main bus for connecting a plurality of DC lines with each other. First and second DC lines are connected between first and second DC networks and the main bus via respective main switches. The DC networks contain a DC operating equipment, such as a converter, an energy storage device, a DC chopper, a DC cable, an energy source and/or a load. A transfer bus that is electrically connected to the main bus has a transfer bus disconnector for disconnecting the main bus from the transfer bus, a transfer switch, and a current limiting device with a resistor and a parallel resistor bypass switch. The first DC line is connected to the transfer bus via a first transfer disconnector and the second DC line is connected to the transfer bus via a second transfer disconnector.

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 device for preparing a high-voltage direct current transmission includes a first busbar which is connectable to a plurality of first energy generation or consumer units and a second busbar which is connectable to a plurality of second energy generation or consumer units. A transformer system includes a first primary coil which is connectable to the first busbar, a second primary coil which is connectable to the second busbar, and a secondary coil system which is inductively coupled to the first primary coil and the second primary coil to transform power routed on the first and second busbars to increased AC voltage. A converter system is connected to the secondary coil system to convert the increased AC voltage into DC voltage for the high-voltage direct current transmission. A converter station and an energy providing system are also provided.

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 device for preparing a high-voltage direct current transmission includes a first busbar which is connectable to a plurality of first energy generation or consumer units and a second busbar which is connectable to a plurality of second energy generation or consumer units. A transformer system includes a first primary coil which is connectable to the first busbar, a second primary coil which is connectable to the second busbar, and a secondary coil system which is inductively coupled to the first primary coil and the second primary coil to transform power routed on the first and second busbars to increased AC voltage. A converter system is connected to the secondary coil system to convert the increased AC voltage into DC voltage for the high-voltage direct current transmission. A converter station and an energy providing system are also provided.

Abstract: A converter assembly includes a converter unit having AC voltage connection points feeding in or tapping an alternating current, and first and second DC voltage connection points feeding in or tapping a direct current. Parallel series circuits associated with an AC voltage connection point each have first and second circuit connection points respective connected to first and second DC voltage connection points. Each series circuit has submodules connected in series. For each series circuit the AC voltage connection point divides submodules into submodule groups electrically close to first and electrically close to second series circuit connection points. One DC voltage connection point is grounded. For each series circuit the AC voltage connection point divides the submodules into a submodule group electrically close to and a submodule group electrically remote from ground. Submodule groups close to ground have a bipolar submodule and submodule groups remote from ground have unipolar submodules.

Abstract: A device for connecting at least one single-phase power supply line which, in particular, feeds the overhead line of a railroad track, to a three-phase power supply network. A primary side of a transformer is connected to the power supply network and a secondary side is connected to the single-phase power supply line and to a ground connection. A symmetry device is connected to a phase of the transformer, to the ground connection, and to the single-phase power supply line.

Abstract: A static converter that includes a power converter circuit having a plurality of interconnected module branches. Each module branch may have one or more electrically series-connected two-pole submodules as switchable voltage sources which each include a capacitor as an energy store and power semiconductors as electronic switching elements. A device for precharging the capacitors is included that has at least one power electronics device for providing an adjustable precharge current. The at least one power electronics device, being supplied with power by an auxiliary supply system and being connected to a converter bridge via a precharge transformer, can be used to achieve a sufficiently high voltage level for the capacitors of the submodules when the converter is started up so as to achieve firstly the minimum voltage for supplying power to the power semiconductors and secondly the minimum voltage for synchronization to the systems.

Abstract: A static converter includes a current converter on the three-phase side and a current converter on the single-phase side, which are electrically conductively linked to one another on the DC voltage side, and which are respectively electrically conductively connected on the AC voltage side to a feeding three-phase network and a single-phase receiving network. According to an embodiment of the invention, one network-commutated current converter is provided as the current converter on the three-phase side, wherein the current converter on the single-phase side has two phase modules which are connected in parallel on the DC voltage side and whose current converter branches each have at least one two-pole subsystem. This results in a static converter which is simpler and costs less than a known static converter.

Abstract: A static converter is disclosed. In at least one embodiment, the static converter includes a power converter circuit which has a plurality of interconnected module branches, wherein each module branch has one or more electrically series-connected two-pole submodules as switchable voltage sources which each include a capacitor as an energy store and power semiconductors as electronic switching elements. A device for precharging the capacitors is included, including at least one power electronics device for providing an adjustable precharge current. The at least one power electronics device, being supplied with power by an auxiliary supply system and being connected to a converter bridge via a precharge transformer, can be used to achieve a sufficiently high voltage level for the capacitors of the submodules when the converter is started up so as to achieve firstly the minimum voltage for supplying power to the power semiconductors and secondly the minimum voltage for synchronization to the systems.

Abstract: A device for connecting at least one single-phase power supply line which, in particular, feeds the overhead line of a railroad track, to a three-phase power supply network. A primary side of a transformer is connected to the power supply network and a secondary side is connected to the single-phase power supply line and to a ground connection. A symmetry device is connected to a phase of the transformer, to the ground connection, and to the single-phase power supply line.

Abstract: A static converter includes a current converter on the three-phase side and a current converter on the single-phase side, which are electrically conductively linked to one another on the DC voltage side, and which are respectively electrically conductively connected on the AC voltage side to a feeding three-phase network and a single-phase receiving network. According to an embodiment of the invention, one network-commutated current converter is provided as the current converter on the three-phase side, wherein the current converter on the single-phase side has two phase modules which are connected in parallel on the DC voltage side and whose current converter branches each have at least one two-pole subsystem. This results in a static converter which is simpler and costs less than a known static converter.

Abstract: The invention relates to a device for communicating with a system (1, 17). Said device has mobile communication means (12, 27) for a cabled or wireless data exchange with the system (1, 17) and an emergency-stop button (4, 20) integrated into an emergency-stop part (11, 26), with said emergency-stop part (11, 26) being hard-wired to the system and forming, permanently coupled to the mobile communication means via a mechanical coupling link, a portable functional unit serving to perform mobile operator control and monitoring functions.

Abstract: The invention relates to a device for communicating with a system (1, 17). Said device has mobile communication means (12, 27) for a cabled or wireless data exchange with the system (1, 17) and an emergency-stop button (4, 20) integrated into an emergency-stop part (11, 26), with said emergency-stop part (11, 26) being hard-wired to the system and forming, permanently coupled to the mobile communication means via a mechanical coupling link, a portable functional unit serving to perform mobile operator control and monitoring functions.

Abstract: A method is for identifying risks as a result of stray currents which flow to ground from a rail which returns a traction current in a track with a DC power supply. In accordance with a first embodiment, in which the voltage between the rail and ground is measured and an increased risk as a result of stray currents is indicated if there is a discrepancy from a voltage reference value, provision is made for the voltage to be measured at a plurality of measurement points along the track and for the measurements to be evaluated in an evaluation center. In accordance with a second embodiment, provision is made for activating a short-circuiter to connect a parallel path to the rail for returning the traction current. The current level in the parallel path is then measured and an increased risk as a result of stray currents is indicated if there is a discrepancy from a current-level reference value.

Abstract: A method is for identifying risks as a result of stray currents which flow to ground from a rail which returns a traction current in a track with a DC power supply. In accordance with a first embodiment, in which the voltage between the rail and ground is measured and an increased risk as a result of stray currents is indicated if there is a discrepancy from a voltage reference value, provision is made for the voltage to be measured at a plurality of measurement points along the track and for the measurements to be evaluated in an evaluation center. In accordance with a second embodiment, provision is made for activating a short-circuiter to connect a parallel path to the rail for returning the traction current. The current level in the parallel path is then measured and an increased risk as a result of stray currents is indicated if there is a discrepancy from a current-level reference value.