DC toughened glass insulator

Abstract

The invention discloses a DC toughened glass insulator, which comprises an iron cap (2), a glass piece (8), a steel pin (4) and adhesive (4), wherein the glass piece (8) is provided with an outer umbrella skirt (11), a first inner umbrella skirt (10) and a second inner umbrella skirt (9), the glass piece (8) comprises the following main chemical compositions in percentage by weight: more than or equal to 18 percent of sodium oxide, more than or equal to 13.67 percent of potassium oxide, more than or equal to 6.1 percent of magnesium oxide, more than or equal to 2.06 percent of barium oxide, more than or equal to 2 percent of aluminum trioxide and rest silicon dioxide. The height ratio between the outer umbrella skirt (11) and the first inner umbrella skirt (10) and between the second inner umbrella skirt (9) and the outer umbrella skirt is less than or equal to 0.6, or the height ratio between the first inner umbrella skirt (10) and the outer umbrella skirt and between the first innerumbrella skirt (10) and the second inner umbrella skirt (9) is more than or equal to 1.5. The DC toughened glass insulator can effectively prevent the ionic migration in the glass piece, reduces the concentration of main charge carriers in the glass piece, hinders the displacement of ions which are easy to migrate in an irregular network inside the glass piece, reduces the migration charge quantity in the glass piece, improves the volume resistance of the toughened glass insulator, reduces the aging speed of the toughened glass insulator, and improves the flashover voltage and the breakdown voltage of the toughened glass insulator under the serious contamination.

Description

Technical field [0001] The invention relates to a toughened glass insulator, in particular to a toughened glass insulator for direct current transmission with ultra-high voltage, large capacity and long distance. Background technique [0002] With the continuous development of science and technology, DC transmission with ultra-high voltage, large capacity, long distance and low line loss has become the development trend of the power industry. In high-voltage and ultra-high voltage AC transmission, the existing disc-shaped suspension type tempered glass fiber reinforced plastic insulators have been widely used, but this type of disc-shaped suspension type tempered glass fiber reinforced plastic insulator cannot be directly applied to UHV DC transmission. This is because Disc-shaped suspension type tempered glass fiber reinforced plastic insulators used in UHV DC transmission still have the following problems: First, the DC line current is different from the AC line current. Under ...

AI Technical Summary

Problems solved by technology

In high-voltage and ultra-high-voltage AC transmission, the existing production of disc-shaped suspended tempered FRP insulators has been widely used, but this disc-shaped suspended tempered FRP insulator cannot be directly applied to ultra-high-voltage direct current transmission. This is because There are still the following problems in the application of disk-shaped suspended tempered glass fiber reinforced plastic insulators in EHVDC transmission: First, the DC line current is different from the AC line current. One-way migration and local ion aggregation cause the aging of tempered glass insulators; the second is to reduce the possibility of tempered glass insulators being broken down by air and effectively improve the flashover voltage and breakdown voltage of tempered glass insulators under heavy pollution. The volume resistance and ion mobility of tempered glass insulators are higher than those of AC circuits; and the steel feet of tempered glass insulators in DC circuits are at the cement interface than in AC circuits. The cement interface is more prone to corrosion, which reduces the mechanical strength of steel feet and tempered glass insulators

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