DE633903C - An electrical capacitor arranged in an oil container with thin conductive layers separated from one another by several insulating inserts protruding beyond their edge - Google Patents

Description

The invention relates to electrical capacitors with thin conductive, through separated several insulating inserts protruding beyond the edge of the coverings Allocations, with the condenser being arranged in an oil container. In this case, the isolation prepares the coverings no difficulties against penetration, especially since you can easily use the insulating inserts

ίο can be dimensioned accordingly. It has, however shown that even at relatively low voltages flashovers along the protruding edges of the insulating inserts occur. The course of these rollovers is from Fig. ι can be seen that a known capacitor in large magnification shows. Only part of the capacitor winding is drawn because it is on the opposite one Edge the ratios are exactly the same.

With ι are the insulating intermediate layers designated. 2 is the one group of capacitor assignments that relate to the same Potential. 3 is the other occupancy group placed at the other potential. To connect the assignments leading to the same potential, how from the assignments 3 can be seen, the over

the edges of the coverings protruding from the insulating inlays overturned and thus conductively connected to one another. In the capacitor shown, a flashover occurs between points A and B at voltages of around 2000 volts, even if the entire capacitor winding is housed in an oil container and air pockets have been removed by carefully pumping out.

It has now been shown that with such capacitors the voltage is considerable can increase without having to worry about a rollover if you have between the between the edges of the insulating inserts protruding beyond the conductive layers dimensioned further than they resulted from the usual method of manufacture. at a capacitor e.g. B. the thickness of the conductive layer is about 0.05 to 0.1 mm, the thickness of the insulating paper interlayers from 0.006 to about 0.006 mm. For higher Tensions, several layers of paper, rarely less than three, are chosen. In the preparation of one tried to wind up the winding as tightly as possible, and thereby achieved that the at the same metallic insert adjoin from opposite sides -

") The patent seeker stated as the inventor:

Dr.-Ing. Hans Ritz in Berlin-Siemensstadt.

60S

the insulating inserts with their protruding edges lay firmly on top of one another. But this apparently favorable appearance is precisely the reason for the low, tension fesjag ^? wedge. It has been shown 'that' - '^ f | Maintaining a sufficient gap between the insulating layers and the edges of the metallic inserts, the dielectric strength increases to surprisingly high values. An explanation can be given for this phenomenon, which is explained with reference to FIG. 2 below. With and 3, the metallic inserts a capacitor are referred to the insulation three layers of paper used-Jaind. ..: 'In contrast to the usual embodiment, the conductive layer i adjacent insulating inserts i are ^fl not led out to the flange of the reel, Rather, they are only a little beyond the leading assignments. Similarly, the subsequent layers i ⁶ .are treated, and is finally in winding of the package, taken care to that der'zwischen the layers i ^'p, insofar as they project beyond the edge of the layer 2, located intermediate space Z is not concentrated . .The. small dimensions the interposition of supports is not possible, the tension of the insulating layers must be chosen during the manufacture of the winding so that /: they do not close the gaps by themselves, for example as a result of their internal tension oil bath. Then '. the with .Z be _; drew gap wide enough to ensure oil renewal. ■ '-;

They are arranged in a "container" filled with an insulating liquid Capacitors have become known, which also take up a relatively large space is provided between the conductive layers. In contrast to the Ge ^ The object of the invention is achieved in that the insulating layers adjacent to the conductive layers Spacers stand back from the conductive layers so that the edges the conductive layers are exposed. The capacitor of this known type is now so sized that the discharges occurring at the edges, a movement within the insulating liquid used for cooling. By exposing the edges of the conductive. Laying prevents electrical discharges reach the solid insulators and they can destroy. ■

In contrast, the object relates of the invention to such capacitors in which the insulating layers over the Edge of the senior. Assignments stand out.

Further, the capacitor is dimensioned in a known manner 'so that the in potential; is ffSchied <tg.gungen separate between two conductive loading kept so low that the Be - "; ajfepruchung of the insulating material beneath the tfSJ ^ r date set out initial voltage is As a result, no discharges occur which could lead to the destruction of the insulating inserts. According to the invention, the gap which is actually formed by the presence of the conductive covering between the adjacent "insulating inserts along the edges of the insulating inserts protruding beyond the covering, widened by the fact that -, _ some- of the 'insulating inserts arranged between two separate assignments protrude only a little beyond the conductive movements.

You can let the insulating inserts i " protrude so far beyond the edge of the metallic layer 2 that a secure storage of this layer is achieved within the paper roll by pressing the sharp edges of the metallic layer.

One can further achieve a widening of the gap according to an advantageous Design of the capacitor according to the invention, the metallic coverings by additional means so that they inherently have a sufficient distance between the insulating layers adjoining them ensure that at the same time care is taken to ensure that the edges are sharp Edges and corners are absent. In the case of a wound capacitor, e.g. Fold the edge of the metal strip several times until you get a bead of sufficient strength • and rounded off. In this case, however, you have to get a smooth winding to get ,, fill the middle of the metallic strip, z. B. by wrapping of correspondingly narrow insulating strips.

Claims (5)

Patent claims: ι-. Arranged in an oil tank electrical capacitor with thin conductive - through several over their edge Outstanding - Isoliereinlageii separate assignments, in which the The botential difference between two separate assignments is kept so low that that the stress on the insulating material is below the initial voltage, thereby characterized in that the gap created in itself by the presence of the conductive Allocation between the adjacent insulating layers along the over the Occupancy protruding edges of the insulating inserts is formed, thereby widened is that some of the between ever two separate assignments arranged insulating inserts only a little over the conductive ones Assignments stand out. 2. 'capacitor according to claim i, dVu characterized in that at least 'the edge of the conductive inserts z. B. by one or more foldings is so strong that the onset of edge discharges as a result of the resulting greater width of the gap between the insulating inserts that adjoins the edge and also as a result of the enlargement the smallest radius of curvature at the edge of the metallic coating is difficult or prevented. 3. Capacitor according to claim 1, characterized in that at least the almost immediately adjacent to the conductive coverings insulating inserts the same amount with the occupancies. 4. wound capacitor according to claim 3 with an even number of intermediate layers between the adjacent conductive coverings, characterized by the use of the same width among them Insulating inserts, which are shifted against each other in relation to the winding width, that of the deposits located between two adjacent conductive assignments cut off one half with one end face and the other half with the other end face of the winding package. 5. Capacitor according to claim 3, characterized in that when used of at least three insulating inserts arranged between two consecutive conductive coverings which are directly the conductive assignments on the insulating inlays adjacent to the conductive assignments protrude by a small amount, while the subsequent insulating insert Cut off or inlays roughly with the edge of the conductive coverings. 1 sheet of drawings