Capacitor bushing and manufacturing method therefor
Disclosed is a capacitor bushing and a method of manufacturing the same. The capacitor bushing includes insulating layers ( 20 ), formed by winding insulating fibers ( 22 ) around the outer side of a central conductor ( 10 ), and conductive layers ( 30 ) between the insulating layers ( 20 ). The wefts ( 34 ) and warps ( 36 ) that constitute the conductive fibers ( 32 ) are manufactured by sequentially forming a first coating layer ( 38 ) and a second coating layer ( 38 ′) on the surface of a core wire ( 37 ). The wefts ( 24 and 34 ) and the warps ( 26 and 36 ) of the insulating fibers ( 22 ) and the conductive fibers ( 32 ) extend obliquely with respect to the longitudinal direction of the central conductor ( 10 ). The wefts ( 24 and 34 ) and the warps ( 26 and 36 ) form a polygonal or circular shape. The present invention has a merit in that bubbles are prevented from being generated in the filling layers ( 40 ).
1. A capacitor bushing comprising:
a central conductor having a predetermined length,
insulating layers formed by winding insulating fibers around an outer side of the central conductor so that wefts and warps constituting the insulating fibers extend obliquely with respect to a longitudinal direction of the central conductor,
conductive layers positioned between the insulating layers and including conductive fibers, and
filling layers formed by filling spaces between the insulating layers and the central conductor, between the insulating layers, and between the insulating layers and the conductive layers with an epoxy resin.
2. The capacitor bushing of claim 1 , wherein the conductive fibers include wefts and warps obtained by sequentially forming a first coating layer and a second coating layer on an outer side of an insulating core wire.
3. The capacitor bushing of claim 2 , wherein the wefts and the warps of the insulating fibers and the conductive fibers are woven so as to form a circular or polygonal shape.
4. The capacitor bushing of claim 3 , wherein the wefts and the warps of the insulating fibers and the conductive fibers are woven so as to form a hexagonal shape.
5. The capacitor bushing of claim 1 , wherein the epoxy resin for forming the filling layers is mixed with 0 to 50 wt % of an inorganic filler.
6. The capacitor bushing of claim 5 , wherein the inorganic filler is silica or alumina.
7. The capacitor bushing of claim 2 , wherein the wefts and the warps constituting the conductive fibers are woven so as to extend obliquely with respect to the longitudinal direction of the central conductor.
8. A method of manufacturing a capacitor bushing, the method comprising:
winding insulating fibers around an outer side of a central conductor to form insulating layers,
interposing conductive fibers between the insulating layers to form conductive layers,
positioning the central conductor, which has the insulating layers wound around the outer side thereof and the conductive layers interposed between the insulating layers, in a mold,
injecting a material for forming filling layers while an inside of the mold is maintained in a vacuum state, thus forming the filling layers, and
curing the filling layers by applying pressure and heat to the mold in a state in which injection of the material for forming the filling layers into the mold is finished in order to form the filling layers,
wherein the insulating fibers are wound so that wefts and warps of the insulating fibers extend obliquely with respect to a longitudinal direction of the central conductor.
9. The method of claim 8 , wherein the conductive fibers are wound so that wefts and warps of the conductive fibers extend obliquely with respect to the longitudinal direction of the central conductor.
10. The method of claim 8 , wherein the material for forming the filling layers is an epoxy resin and an inorganic filler is mixed in an amount of 0 to 50 wt %.
11. The method of claim 8 , further comprising:
cooling the filling layers after the curing the filling layers.