Abstract:
An apparatus switches a direct current in a high-voltage line. The apparatus contains a multiplicity of switching units, which are arranged so as to form a series circuit in the high-voltage line. Each switching unit in this case contains a switching element and a surge arrester arranged in a parallel circuit with the switching element, the threshold voltage of the surge arrester being higher than a rated voltage of the switching element. A sum of the rated voltages of the switching elements corresponds at least to an operating voltage of the high-voltage line. The switching elements are mechanical switches, and each mechanical switch contains a contact arrangement having two disconnectable contact pieces and is configured to build up an arcing voltage on disconnection of the contact pieces with a magnitude which is higher than the rated voltage of the mechanical switch.
Abstract:
A device switches a direct current. The device contains an operating current branch in which a mechanical switch is arranged, a protective switch connected to the operating current branch for interrupting the current flow in the operating current branch, a capacitor branch connected in parallel with the operating current branch in which capacitor branch a capacitor is arranged, and a damping apparatus which has a resistance element. The damping apparatus is arranged in the capacitor branch in series with the capacitor or in the operating current branch in series with the mechanical switch, which damping apparatus can be bypassed by a bypass switch connected in parallel with the damping apparatus.
Abstract:
A device controls a load flow in an alternating-voltage network. The device is distinguished by a module series circuit of two-pole switching modules that can be inserted in series into a phase line of the alternating-voltage network. Each switching module has an energy store and controllable power semiconductors that can be switched on an off and each switching module can be controlled in such a way that a switching-module voltage can be produced at the poles thereof, which switching-module voltage corresponds to a positive or negative energy-store voltage or a voltage having the value of zero. A control apparatus for controlling the switching modules is provided, which control apparatus is configured to control the switching modules in such a way that a periodic longitudinal voltage can be produced at the module series circuit. A method for controlling a load flow in an alternating-voltage network is performed by the device.
Abstract:
A measuring device measures an electrical current and contains a light source for generating a polarized primary light signal for feeding into a Faraday sensor unit, and a detector for detecting a secondary light signal provided by the Faraday sensor unit and polarization-altered in relation to the primary light signal. An optical-electrical compensation element, by which the polarization alteration of the secondary light signal can be compensated via an opposite polarization alteration, and a measurement signal, according to the opposite polarization alteration, for the electrical current can be deduced. A method for measuring an electrical current by use of the measuring device is further disclosed.
Abstract:
An actuating device for a vacuum switching tube has a connecting element which can be connected to an electric contact of the vacuum switching tube, an electromagnetic actuating device for displacing the connecting element between a first and a second position, and a retaining yoke, relative to which the connecting element can be displaced and has a first magnetic element. The first magnetic element generates a first and a second magnetic circuit in the retaining yoke. The actuating device further has a ferromagnetic retaining anchor, which is arranged on the connecting element. The retaining anchor is located in the first position of the connecting element in the first magnetic circuit and in the second position of the connecting element in the second magnetic circuit. The connecting element is held in the first and in the second position by a respective magnetic force between the retaining yoke and the retaining anchor.
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:
A commutating circuit for an electronic power converter has a first switching device, by which the electronic power converter can be electrically bridged, and a circuit part for limiting the size of the time-related voltage change of a voltage present on the first switching device. The circuit part limits the time-related voltage variation.
Abstract:
An actuating device for a vacuum switching tube has a connecting element which can be connected to an electric contact of the vacuum switching tube, an electromagnetic actuating device for displacing the connecting element between a first and a second position, and a retaining yoke, relative to which the connecting element can be displaced and has a first magnetic element. The first magnetic element generates a first and a second magnetic circuit in the retaining yoke. The actuating device further has a ferromagnetic retaining anchor, which is arranged on the connecting element. The retaining anchor is located in the first position of the connecting element in the first magnetic circuit and in the second position of the connecting element in the second magnetic circuit. The connecting element is held in the first and in the second position by a respective magnetic force between the retaining yoke and the retaining anchor.
Abstract:
A converter has module devices each with a series connection of at least two partial modules being electrically connected in series. A central device is configured to switch module control devices, in which a sum of the transmitted voltage values or the transmitted sum value reaches a predefined voltage threshold, into a second charging phase of a charging operation by transmitting a first voltage specification relating to switched-off partial modules and a second voltage specification relating to switched-on partial modules to the module control devices. The module devices are configured to meet the first and second voltage specifications by setting none, one or more of the communication-capable partial modules thereof into a switched-on operating state and none, one or more of the other communication-capable partial modules thereof into a switched-off operating state, and to continue the charging of the energy stores which are in the switched-on and blocked operating state.
Abstract:
A device for switching a direct current includes an operating current path which has a mechanical switch, a switch-off current path which is connected in parallel to the operating current path and has a power-electronic switch, and a commutation device which allows commutation of the direct current from the operating current path into the switch-off current path. The commutation device includes a transformer.