Abstract:
A magnetic core for an electrical device comprises at least one metal layer, wherein the metal layer comprises a metal coated with a silica based coating.
Abstract:
In einem supraleitenden Strombegrenzer 1 werden im Begrenzungsfall durch Verdampfen von Kühlflüssigkeit Druckwellen erzeugt, welche den Supraleiter schädigen können. Erfindungsgemäss wird der Strombegrenzer nicht in eine Kühlflüssigkeit eingetaucht, sondern mit einem Kühlfluid 22 in thermischen Kontakt gebracht, welches oberhalb der Betriebstemperatur keinen Phasenübergang aufweist, und somit im Begrenzungsfall nicht verdampft. Ein Kältereservoir 21, welches die kondensierte Phase eines gasförmigen Kühlfluids oder ein Kryokühler sein kann, bestimmt die Betriebstemperatur des Strombegrenzers. Ein Vorteil besteht darin, dass nun auch mehrere und unbeschränkt grosse plattenförmige Strombegrenzermodule 10,10' nebeneinander in dem Kühlfluid 22 angeordnet werden können.
Abstract:
Die vorliegende Erfindung betrifft eine Supraleiteranordnung, insbesondere einen supraleitenden Strombegrenzer, und seine dazugehörige Kühlanordnung. Um zu vermeiden, dass bei einer durch einen Fehlerstrom verursachten Erwärmung des Supraleiters flüssiger Stickstoff 21 verdampft und die Supraleiteranordnung 10 mechanisch belastet wird, ist zwischen dem Supraleiter und dem Flüssigstickstoffreservoir ein Kältemoderator 22 vorgesehen. Dieser weist einen begrenzenden Moderatorquerschnitt 222 auf, welcher eine Kühlung der Anordnung im Dauerbetrieb ermöglicht, aber verhindert, dass die im Fehlerfall entstehende Wärmemenge an das Flüssigstickstoffreservoir weitergeleitet wird. Bevorzugt weist der Kältemoderator 22 ein poröses oder saugfähiges Material zur Aufnahme oder Tränkung mit Kühlflüssigkeit auf.
Abstract:
High voltage switching device comprising an outer casing, and a current interruption assembly comprising at least one vacuum chamber which is positioned inside the outer casing, a fixed contact assembly comprising a first fixed contact and a second fixed contact positioned inside the vacuum chamber, first and second movable-contact assemblies comprising a first movable contact and a second movable contact, respectively. A single mechanism actuates the first and second movable-contact assemblies between a first position in which the first and second movable contacts are electrically coupled inside the at least one vacuum chamber with the first fixed contact and the second fixed contact, respectively, and a second position in which they are electrically separated there from. The first movable contact assembly, the second movable contact assembly and the actuating mechanism are arranged so as the first movable contact and the second movable contact move, along a reference axis, one towards the other when switching from the second position to the first position and one away from the other when switching from the second position to the first position.
Abstract:
The invention relates to a nonlinear field control tape containing ZnO microvaristor particles. The doped ZnO particles are produced by crushing a sintered ZnO block, by desagglomeration or crushing of calcinated granulated particles, or by crushing of a calcined or sintered tape (tape casting). Embodiments, among other things, relate to: hollow ZnO microvaristor particles produced by granulation technique, having reduced average density and having diameters in a range well below 90 µm; and compounding the ZnO filler in binders that are used to impregnate tapes. Compared to nonlinear field control tapes with conventional embedded nonlinear filler particles, a stronger and more reliable nonlinear resistivity is achieved and the ZnO filler is simpler to produce and to compound in the binder. The resulting tapes are flexible, preferably self-adhesive and have a strong nonlinear electrical resistivity. The tapes are useful to protect high field-stress regions in electrical components.
Abstract:
The invention relates to a nonlinear electrical material with improved microvaristor filler (1'), to devices and electrical apparatuses comprising such nonlinear electrical material and to a production method thereof. According to invention, the filler (1') comprises larger spherical particles (5) and smaller irregular particles (6) that are arranged interstitially and provide non-point-like and/or multiple contact areas (56, 56a, 56b, 66) owing to their irregular outer shape comprising edges and faces. Embodiments, among other things, relate to: spherical particles (5) being calcinated and broken-up to retain their original shape; irregular, spikly shaped, particles (6) obtained by calcinating or sintering and crushing or fracturing granules or blocks; and addition of a third filler fraction. Advantages, among others, are: higher filler contents, more and more durable inter-particle contacts (56, 56a, 56b, 66), enlarged effective micro-contact area, and improved electrical performance of the nonlinear electrical material.
Abstract:
The present invention is concerned with a superconducting fault current limiter comprising a composite consisting of high-temperature superconductor layer (11) and electrical bypass layer (12), and a thermal barrier (3) provided between the conductor and surrounding cooling fluid (4). The transfer of the heat generated in the composite during a fault event is delayed and smoothed, thus preventing the creation of shock or pressure waves in the cooling fluid. The thermal barrier is preferably composed of a pressboard impregnated by a polymer resin.