Insulating wire having partial discharge resistance and high partial discharge inception voltage
The present invention relates to an insulating wire and, more particularly, to an insulating wire having partial discharge resistance that exhibits excellent partial discharge resistance and high partial discharge inception voltage and also excellences in the adhesion between the conductor and the insulation layer and the flexibility of the insulation layer, which insulating wire can be prepared by a simple process at a low production cost.
1. An insulating wire having partial discharge resistance, comprising a conductor and an insulation layer,
the insulation layer being disposed to cover around the conductor and containing a polymer base resin and inorganic particles, the polymer base resin including at least one of a polyimide resin and a polyamide imide resin,
the content of the inorganic particles being 10 to 30 parts by weight with respect to 100 parts by weight of the polymer base resin, and
the inorganic particles comprising 10 to 60 parts by weight of dry zeolite particles and 40 to 90 parts by weight of inorganic nanoparticles with respect to 100 parts by weight of the inorganic particle,
wherein the dry zeolite particles have a porosity of 18 to 50% with respect to a total volume thereof, and each has a diameter of 1 to 10 μm,
wherein the inorganic nanoparticles includes at least one of silica, alumina, titanium dioxide, zirconia, yttria, mica, clay, chromium oxide, zinc oxide, iron oxide, magnesium oxide, calcium oxide, scandium oxide, and barium oxide, and each is pore free and has a diameter of 4 to 50 nm,
wherein the insulation layer contains air filled in micropores of the dry zeolite particles and has a dielectric constant in a range of 2.5 to 3.
2. The insulating wire having partial discharge resistance as claimed in claim 1 , wherein the dry zeolite particles have an inner porosity of 45 to 55% and an outer porosity of 30 to 40% out of the total porosity.
3. The insulating wire having partial discharge resistance as claimed in claim 2 , wherein the dry zeolite particles are prepared by processing at least one synthetic zeolite selected from the group consisting of Na 12 [(AlO 2 ) 12 (SiO 2 ) 12 ].27H 2 O, Na 4 TMA 3 [(AlO 2 ) 7 (SiO 2 ) 17 ].21H 2 O, Na 8 TMA[(AlO 2 ) 9 (SiO 2 ) 15 ].28H 2 O, Na 86 [(AlO 2 ) 86 (SiO 2 ) 106 ].264H 2 O, Na 56 [(AlO 2 ) 56 (SiO 2 ) 136 ].250H 2 O, (Na 2 , K 2 , Ca, Mg) 29.5 [(AlO 2 ) 59 (SiO 2 ) 133 ].235H 2 O and Ca 2 [(AlO 2 ) 4 (SiO 2 ) 8 ].13H 2 O to a micro-scaled size and then dehydrating and drying by heat.
4. The insulating wire having partial discharge resistance as claimed in claim 1 , wherein the conductor has a round or flat cross section.
5. The insulating wire having partial discharge resistance as claimed in claim 1 , wherein the insulation layer comprises at least one adhesive agent selected from the group consisting of a melamine-based compound, an amine-based compound, a mercaptan-based compound and a polycarbodiimide-based compound in an amount of 1 to 3 parts by weight with respect to 100 parts by weight of the polymer base resin.