Abstract:
An extinguishing branch (28) for an electrical circuit (32) includes: a snubber circuit (36) including an energy storage limb (40), wherein the energy storage limb (40) includes first and second energy storage limb portions separated by a first junction (46) to define a first voltage divider, and each energy storage limb portion includes at least one energy storage device (48,50); and an arrester limb (38) connected across the energy storage limb (40), wherein the arrester limb (38) includes first and second arrester limb portions separated by a second junction (52) to define a second voltage divider, and each arrester limb portion includes at least one arrester element (54,56), wherein the first and second junctions (46,52) are connected to define a voltage divider bridge, and the voltage divider bridge is electrically coupleable to the electrical circuit (32) so as to provide, in use, a driving voltage to drive the electrical circuit (32).
Abstract:
A control circuit comprising: first and second terminals for respective connection to first and second power transmission lines; a current transmission path extending between the first and second terminals and having first and second current transmission path portions separated by a third terminal, either or both of the first and second current transmission path portions including at least one module, the or each module including at least one energy storage device; an auxiliary terminal for connection to ground or the second power transmission line; an energy conversion block for removing energy from the power transmission lines, the energy conversion block extending between the third and auxiliary terminals such that the energy conversion block branches from the current transmission path, the energy conversion block including at least one energy conversion element; and a control unit which selectively removes the or each energy storage device from the current transmission path.
Abstract:
An electrical field shielding assembly comprises at least one electrically conductive, shielding element (12) that is hingably mounted on the electrical field shielding assembly, wherein the or each shielding element (12) is hingably movable between an open position in which an access opening in the electrical field shielding assembly is created and a closed position in which the access opening in the electrical field shielding assembly is closed.
Abstract:
A control circuit (20) comprises: first and second terminals (22,24) for respective connection to first and second power transmission lines (26,28); a current transmission path (30,32) extending between the first and second terminals (22,24), the current transmission path (30,32) including at least one module (36), the or each module (36) including at least one energy storage device, the current transmission path (30,32) including at least one inductor (38); a control unit (46) which selectively removes the or each energy storage device of the or each module from the current transmission path (30,32) to modulate a voltage across the or each inductor (38) in a filtering mode to modify current flowing through the current transmission path (30,32) and thereby filter one or more current components from the power transmission lines (26,28); and at least one energy conversion element, wherein the control unit (46) selectively removes the or each energy storage device of the or each module (36) from the current transmission path (30,32) in an energy removal mode to cause current to flow from the power transmission lines (26,28) through the current transmission path (30,32) and into the or each energy conversion element to remove energy from the power transmission lines (26,28).
Abstract:
An electrical apparatus (10) comprises: first and second terminals (18,20) for connection to an electrical circuit; a chain-link converter (22) connected between the first and second terminals (18,20), the chain-link converter (22) including a plurality of chain-link modules (24), each chain-link module (24) inluding at least one switching element (26) and at least one energy storage device (28), the or each switching element (26) and the or each energy storage device (28) of each chain-link module (24) combining to selectively provide a voltage source; and a protection device (32) connected across an electrical block (34) that includes at least two of the plurality of chain-link modules (24), the protection device (32) including a plurality of series-connected semiconductor devices (36), wherein the protection device (32) selectively provides a current-conductive path to allow at least part of a current flowing in the electrical apparatus (10) to bypass the electrical block (34).
Abstract:
An extinguishing branch (28) for an electrical circuit (32) includes: a snubber circuit (36) including an energy storage limb (40), wherein the energy storage limb (40) includes first and second energy storage limb portions separated by a first junction (46) to define a first voltage divider, and each energy storage limb portion includes at least one energy storage device (48,50); and an arrester limb (38) connected across the energy storage limb (40), wherein the arrester limb (38) includes first and second arrester limb portions separated by a second junction (52) to define a second voltage divider, and each arrester limb portion includes at least one arrester element (54,56), wherein the first and second junctions (46,52) are connected to define a voltage divider bridge, and the voltage divider bridge is electrically coupleable to the electrical circuit (32) so as to provide, in use, a driving voltage to drive the electrical circuit (32).
Abstract:
A switching device (28) comprising a primary switching block (30) including at least one semiconductor switch (34); and a switching control unit (32) to control the switching of the or each semiconductor switch (34). The switching device further includes a crowbar circuit (46) comprising a crowbar switch (56) switchable to selectively allow current to flow through the crowbar switch (56) in order to bypass the or each switching module; and a secondary switching block including a switching element (58) connected across a control electrode and a cathode of the crowbar switch (56). The switching element (58) is in communication with the switching control unit (32) to receive, in use, a control signal (66) generated by the switching control unit (32) when the primary switching block (30) is operating within predefined operating parameters.
Abstract:
A control circuit (20) comprising: first and second terminals (22,24) for respective connection to first and second power transmission lines (26,28); a current transmission path extending between the first and second terminals (22,24) and having first and second current transmission path portions (30,32) separated by a third terminal (34), either or both of the first and second current transmission path portions (30,32) including at least one module (36), the or each module (36) including at least one energy storage device; an auxiliary terminal (42) for connection to ground or the second power transmission line (28); an energy conversion block for removing energy from the power transmission lines (26,28), the energy conversion block extending between the third and auxiliary terminals (34,42) such that the energy conversion block branches from the current transmission path, the energy conversion block including at least one energy conversion element (44); and a control unit (46) which selectively removes the or each energy storage device from the current transmission path.
Abstract:
There is a control circuit comprising first and second DC terminals for connection to a DC network, the first and second DC terminals having a plurality of modules and at least one energy conversion element connected in series therebetween to define a current transmission path, the plurality of modules defining a chain-link converter, each module including at least one energy storage device, the or each energy storage device being selectively removable from the current transmission path to cause a current waveform to flow from the DC network through the current transmission path and the or each energy conversion element and thereby remove energy from the DC network, the or each energy storage device being selectively removable from the current transmission path to modulate the current waveform to maintain a zero net change in energy level of the chain-link converter.