TRANSFORMER
FIG10 is a comparison diagram illustrating the electric field distribution of the insulated structure in FIG6 versus the electric field distribution of the insulated structure in FIG7
In order to compare the electric field distributions of the two insulated structures more intuitively, a changing curve of electric field is drafted by starting from a center of circle, along the radial direction, as illustrated in FIG10. In FIG10, the horizontal coordinate indicates the radius while the vertical coordinate indicates the electric field intensity. The solid-line curve illustrates an electric field distribution condition of the second solution in the prior art technology. It can be seen that, the insulated structure has a greater electric field value at an inner side (an external surface of the grounded aluminum pipe, at a horizontal coordinate position of 5mm), with a maximum value of 2.9 kV/mm, and the insulated structure has an extremely small electric field value at an external side ,with a value smaller than 0.5 kV/mm, and at a horizontal coordinate position greater than 17mm; that is, the electric field distribution is extremely uneven. The dash-line curve illustrates the electric field distribution condition of the embodiment of the present disclosure, in which the maximum electric field is located at an interface (at a horizontal coordinate position of 12mm) of the second solid insulating layer with the air, having a maximum value of 1.9 kV/mm, and an inner side of the second solid insulating layer has relatively smaller electric field (the maximum value is 1.2 kV/mm, and the horizontal coordinate position is smaller than 10mm). Compared with the second solution in the prior art technology, the maximum electric field value in the present disclosure is reduced: it reduced from 2.9 kV/mm to 1.9 kV/mm; meanwhile, the entire electric field distribution is more uniform. Thus, as compared with the second solution in the prior art technology, the embodiment of the present disclosure optimizes the entire insulation coordination.
diagram
5
air
9
insulated wire
25
semi-conductive layer
10
cores core
15
applied voltage is
['1. A transformer, comprising: at least one magnetic core (6, 10, 13, 16), each having at least one window (A); one primary side winding (9) passing through the at least one window (A) of each of all the magnetic core (6, 10, 13, 16); and at least one secondary side winding (7, 8), each passing through the at least one window (A) of one corresponding magnetic core (6, 10, 13, 16), wherein a wire (1) forms the primary side winding (9), and the wire (1) is sequentially covered with a first solid insulating layer (2), a grounded shielding layer (3) and a second solid insulating layer (4) from inside to outside along a radial direction of the wire (1), wherein the grounded shielding layer (3) is connected to a reference ground, wherein the primary side winding (9) has a first voltage with respect to the reference ground, the secondary side winding (7, 8) has a second voltage with respect to the reference ground, and the second voltage is greater than 50 times of the first voltage.', '9. The transformer according to claim 1, wherein a space between the grounded shielding layer (3) and the second solid insulating layer (4) is further covered with a semi-conductive layer.']