摘要 |
The present invention refers to a power transformer/reactor comprising at least one winding (1, 2, 3). The winding/windings (1, 2, 3) are manufactured with a high voltage cable (10), comprising an electric conductor, around the conductor there being arranged a first semiconducting layer (14), around the first semiconducting layer (14) there being arranged a first insulating layer (16) and around the first insulating layer (16) there being arranged a second semiconducting layer (18). The second semiconducting layer (18) is directly earthed (32, 34) at n points of each winding (1, 2, 3) wherein n is an integral number and n>/=2, and whereby two (32, 34) of said n directly earthed points are arranged at or in the vicinity of both ends of each winding (1, 2, 3) and the electric contact is interrupted (20) 2(n-1) number of times between both ends in the semiconducting layer (18). At each said interruption (20) there is arranged a means (24, 26) comprising a second insulating layer (24) and third semiconducting layer (26) in order to reduce the amplification of electric field strength at said interruption (20). The second semiconducting layer (18) of different phases (1, 2, 3) at each said interruption (20) is earthed in a cross-connected manner (42, 44). Besides, at least one point (36, 38) between both ends is indirectly earthed. |