Abstract: A switching valve includes series-connected switching elements and auxiliary circuits. Each auxiliary circuit is connected in parallel with a respective one of the series-connected switching elements. Each auxiliary circuit includes a respective auxiliary capacitor. The method includes carrying out a compensation procedure. The compensation procedure includes: initiating a turn-off event by sending a respective turn-off control signal to each switching element; measuring a respective capacitor voltage value of each auxiliary capacitor after the turn-off event; comparing the measured capacitor voltage values; and using the comparison between the measured capacitor voltages as a reference to adjust the time of sending a or a respective turn-off control signal to at least one of the switching elements so as to reduce a or a respective time difference between the turn-off times of the switching elements at the next turn-off event.

Abstract: Fault protection of a voltage source converter is provided. An apparatus has a chain-link circuit in series with a director switch. The chain-link circuit includes cells including an energy storage element and cell switching elements connected with anti-parallel diodes. Each cell switching element has a cell switching element controller. The director switch includes director switch units, each having a director switching element and a director switch unit controller. Each cell switching element controller monitors for a fault current and turns-off its associated cell switching element and reports a fault event to a fault controller. Each director switch unit controller monitors for a fault current and reports a fault event to the fault controller but the director switch unit control keeps its associated director switching element turned-on. The fault controller monitors for reports of fault events to order the cell switching elements of at least some of the cells to turn-off.

Abstract: A converter includes first and second DC terminals for connection to a DC network, limb(s) connected between the first and second DC terminals, and a controller. Each limb includes a phase element and DC side sub-converter(s). The phase element has switching elements and AC terminal(s) for connection to an AC network, the switching elements being switchable to selectively interconnect a DC side voltage at a DC side of the phase element and an AC side voltage at an AC side of the phase element, The DC side sub-converter(s) connected to the DC side of the phase element. The controller selectively controls the switching elements and the operation of each DC side sub-converter as a voltage synthesiser. The controller also controls the switching elements to provide a blocking voltage to limit or block the flow of a fault current between the AC and DC networks and through each limb.

Abstract: Fault protection of a voltage source converter is provided. An apparatus has a chain-link circuit in series with a director switch. The chain-link circuit includes cells including an energy storage element and cell switching elements connected with anti-parallel diodes. Each cell switching element has a cell switching element controller. The director switch includes director switch units, each having a director switching element and a director switch unit controller. Each cell switching element controller monitors for a fault current and turns-off its associated cell switching element and reports a fault event to a fault controller. Each director switch unit controller monitors for a fault current and reports a fault event to the fault controller but the director switch unit control keeps its associated director switching element turned-on. The fault controller monitors for reports of fault events to order the cell switching elements of at least some of the cells to turn-off.

Abstract: Methods and apparatus for providing power for a gate signal for a semiconductor switching element are described. In some examples, an alternating current is provided on a primary conductor and induces a current in a secondary conductor. Power is derived therefrom to provide a gate signal. A frequency modulation is applied to the alternating current on the primary conductor and detected in the induced current in the secondary conductor. In some examples, the frequency modulation may be indicative of a data signal, for example a gate control signal.

Abstract: A redundant sensor includes at least two sensing elements. The redundant sensor includes methods and apparatus for time-stamping and combining data from the sensing elements. A method of use and additional embodiments are disclosed.

Abstract: A roof flashing for or suitable for flashing a “ridgeline” as herein defined, the flashing being of multiple materials and being at least in part laminated and comprising or including a “ridge” overlying region to overlie the actual or phantom “ridge” to be flashed, the ridge being as herein defined, a first flanking region extending from the ridge overlying region, and a second flanking region extending from the ridge overlying region, wherein the ridge overlying region is conformed to a retainable three dimensional form and/or is conformable and can retain to a three dimensional form, and wherein the first and second flanking regions extend from the ridge overlying region so as to flank the actual or phantom “ridge” to be flashed by the flashing, and wherein there is a weathering surface of one or more weathering material(s) and at least one of the flanking regions has at least a partial underlying support of the weathering material(s).

Abstract: A building cladding has a cladding material (6) which is fusible and which attached to fastening (7) by fusing. The fastening penetrating the building substrate (4). By fusion to itself the cladding material forms a generally continuous membrane over the substrate. Preferably polyurethane is used as the cladding material fusible surface.

Abstract: A meeting aid (10) configured to facilitate the identification of persons in attendance at a meeting, said meeting aid being one of a set of such meeting aids each for allocation to a said person in attendance at a meeting, the meeting aid comprising: a data input device (60) configured to allow the person to whom the meeting aid has been allocated to input information identifying themselves; communication means (65) for receiving identifying information from one or more of the other meeting aids of said set of meeting aids; a processor (70) configured to process and save received identifying information and identifying information inputted by the person to whom the meeting aid has been allocated, said saved identifying information providing the person to whom the meeting aid has been allocated with a list comprising at least a portion of the identifying information associated with those persons to whom each meeting aid of the set of meeting aids has been allocated; and display means (50) responsive to