Vacuum switching unit and vacuum circuit breaker
A vacuum switching unit of a vacuum circuit breaker has a vacuum interrupter, an insulating sleeve which surrounds the vacuum interrupter, extends tubularly about a longitudinal axis of the vacuum interrupter and is made of an insulating material. A plurality of capacitor electrodes are integrated into the insulating sleeve.
1 . A vacuum switching unit of a vacuum circuit breaker, the vacuum switching unit comprising:
a vacuum switching tube having a longitudinal axis;
an insulating sleeve formed of an insulating material, said insulating sleeve surrounding said vacuum switching tube in a tubular form around the longitudinal axis of said vacuum switching tube;
a plurality of capacitor electrodes integrated into said insulating sleeve; and
a coating disposed on at least one of a region of a surface of said vacuum switching tube that faces toward said insulating sleeve or at least one region of a surface of said insulating sleeve that faces toward said vacuum switching tube, said coating being configured to homogenize an electrical field between said insulating sleeve and said vacuum switching tube.
2 . The vacuum switching unit according to claim 1 , wherein said capacitor electrodes extend in an annular or partially annular arrangement around the longitudinal axis of said vacuum switching tube.
3 . The vacuum switching unit according to claim 1 , wherein said capacitor electrodes form electrode pairs of concentrically extending said capacitor electrodes having mutually facing electrode surfaces and said electrode pairs of concentrically extending capacitor electrodes are disposed at an axial spacing distance from one another relative to the longitudinal axis of said vacuum switching tube.
4 . The vacuum switching unit according to claim 3 , wherein each said electrode pair of concentrically extending capacitor electrodes is formed of a capacitor electrode that extends on a surface of said insulating sleeve facing towards said vacuum switching tube and a capacitor electrode that extends on a surface of said insulating sleeve facing away from said vacuum switching tube.
5 . The vacuum switching unit according to claim 4 , wherein said concentrically extending capacitor electrodes are formed of electrically conductive coating layers applied to said insulating sleeve.
6 . The vacuum switching unit according to claim 3 , wherein said electrode pairs of capacitor electrodes with mutually facing electrode surfaces form capacitors that are connected in series by electrical wires integrated in said insulating sleeve.
7 . The vacuum switching unit according to claim 1 , wherein said plurality of capacitor electrodes include capacitor electrodes that extend inside said insulating sleeve axially at a distance from one another in relation to the longitudinal axis of said insulating sleeve and that have mutually facing electrode surfaces.
8 . The vacuum switching unit according to claim 1 , further comprising at least one electrical resistor integrated into said insulating sleeve and connected, by electrical wires integrated in said insulating sleeve, in series or in parallel with at least one capacitor formed of two capacitor electrodes.
9 . The vacuum switching unit according to claim 1 , wherein said vacuum switching tube comprises at least one shield electrode that is electrically conductively connected and/or capacitively electrically coupled to a capacitor electrode.
10 . The vacuum switching unit according to claim 1 , wherein said insulating sleeve is made from a thermoplastic or from epoxy resin that includes a permittivity-increasing filler.
11 . The vacuum switching unit according to claim 1 , wherein said insulating sleeve, together with said capacitor electrodes, is a 3D-printer printed element.
12 . The vacuum switching unit according to claim 1 , wherein said insulating sleeve is formed of at least two sleeve parts.
13 . A vacuum circuit breaker, comprising at least one vacuum switching unit according to claim 1 .
14 . A vacuum circuit breaker, comprising a plurality of vacuum switching units, each according to claim 1 , and said vacuum switching units having switching paths that are electrically connected in series.