Abstract: A sub-module for a modular multi-stage converter has an energy store and a power semiconductor series circuit connected in parallel to the energy store. In the semiconductor series circuit, two power semiconductor switches that can be activated and deactivated and have the same forward direction are connected in series. A free-wheeling diode is connected in parallel and in the opposite direction to each power semiconductor switch. A first connection terminal is connected to the energy store. A second connection terminal is connected to a potential point between the power semiconductor switches and to the free-wheeling diodes thereof. A bridging switch is disposed between the connection terminals for bridging the sub-module. The power semiconductors thereof are not destroyed upon closing the bridging switch and at least one connection terminal and/or a bridging branch that connects the two connection terminals to each other has an inductive component.

Abstract: In order to be able to eliminate a fault on a high-voltage DC line with an AC voltage supply system which is connected via a self-commutated converter in a reliable manner with a comparatively low level of expenditure, the short-circuiting current flowing in the event of the fault is reduced by way of driving in each case at least one H-bridge submodule in phase branches of the converter, which is of modular design, so as to generate a counter-voltage to the voltage across the arc. There is also provide a system for transmitting an electric current via a high-voltage DC line, and also a converter.

Abstract: A motor drive circuit for a rail vehicle has a step-up converter, which is disposed at the input of the motor drive circuit, and which converts a mains DC voltage, at the input of the motor drive circuit into an intermediate circuit DC voltage. A pulse rectifier, which is downstream from the step-up converter, can be connected at the output to a drive motor of the rail vehicle and it is capable of converting the intermediate circuit DC voltage of the step-up converter into a motor drive voltage for driving the drive motor. A control unit activates the step-up converter in operation such that the converter generates the predetermined rated intermediate circuit DC voltage for a mains DC voltage below a predetermined rated intermediate circuit DC voltage as the intermediate circuit DC voltage.

Abstract: A submodule for a high-voltage converter with reduced risk of cross-ignition includes first and second series-connected energy storage devices, first and second semiconductor series circuits connected in parallel with the energy storage devices, respectively, and having first and second, and respectively third and fourth, switched power semiconductor switching units. A first terminal connects to a first potential point between the first and second switching units, a second terminal connects to a second potential point between the third and fourth switching units. A connecting switching unit is connected between the first and second semiconductor series circuits. A first connecting branch with a first diode connects the first potential point and the potential point between the energy storage devices. A second connecting branch with a second diode connects the second potential point and the potential point between the energy storage devices.

Abstract: A device converts electrical energy into heat in the field of drive voltage technology and/or high voltage technology. The device contains a brake resistance and at least one controllable brake power semiconductor for controlling the conversion, enabling a rapid and economical transformation of effective power into heat as required. To this end, the brake resistance contains a plurality of individual brake resistances that are each part of a bipolar submodule. The submodules are connected in series, form a submodule series connection, and at least partially contain an energy accumulator respectively connected in parallel to an associated individual brake resistance and a controllable brake power semiconductor, which allows the current flow over the respectively associated individual brake resistance in a brake position, and interrupts the current flow over the brake resistance in a normal operating position.

Abstract: A motor drive circuit for a rail vehicle has a step-up converter, which is disposed at the input of the motor drive circuit, and which converts a mains DC voltage, at the input of the motor drive circuit into an intermediate circuit DC voltage. A pulse rectifier, which is downstream from the step-up converter, can be connected at the output to a drive motor of the rail vehicle and it is capable of converting the intermediate circuit DC voltage of the step-up converter into a motor drive voltage for driving the drive motor. A control unit activates the step-up converter in operation such that the converter generates the predetermined rated intermediate circuit DC voltage for a mains DC voltage below a predetermined rated intermediate circuit DC voltage as the intermediate circuit DC voltage.