VACUUM CAPACITOR WITH CORONA RING

The present invention relates to a vacuum capacitor (1, 30) comprising an enclosure (9) to contain a vacuum dielectric medium, a first electrode (12) and a second electrode (13) separated by said vacuum dielectric medium, the enclosure (9) comprising a first conductive collar (2) in electrical contact with the first electrode (12) and a second conductive collar (3) in electrical contact with the second electrode (13), the first conductive collar (2) and the second conductive collar (3) being separated by an insulating element (4) of the enclosure(9), wherein the enclosure (9) exhibits at least one protruding edge (6), said protruding edge (6) being in electrical contact with the closest of the first conductive collar (2) or the second conductive collar (3), wherein the vacuum capacitor (1, 30) comprises at least one protection means (7, 37) covering the protruding edge (6), wherein the protection means (7, 37) is made at least partially of an elastically deformable material, wherein at least the outer surface (7b, 37b) of the protection means (7, 37) is electrically conductive and is at the same electrical potential as the closest conductive collar to the protruding edge (6), and wherein the outer surface (7b, 37b) of the protection means (7, 37) has a radius of curvature greater than the radius of curvature of the protruding edge (6).