Davêkên Transformer: Fonksiyon, Struktur, Tîp & Bihastkirina

1. Pênjaşên Transformer Bushings

Pênjaşa sereke ya transformer bushings-ê dikevên koyeyên koyeyên navendekan derveyên deyîn çêkirin. Wan divê ji bo komponentên îsolan û pêşk kirina navendekan an jî navendekan ser tanka oil.

Dema xebitandina transformer, bushings dê bêtirin taybetên kargû yên hêviya ve ve biçin û, eger ku birhêlka derveyî ye, dê bêtirin taybetên kargû yên şertbendîn. Bunaqela, transformer bushings divê li ser mîn vê berdestan:

• Îmkanên elektrikî yên belavkirin û taybetên mekanîkî yên dest pêk;

• Stabilita çewtî yên welatî yên bikar ên bi viriya çewtî yên dema şertbendîn;

• Struktura kompakt û kêşî, performansa îsolan rêzdar, taybetên bikar ên, û asayîşe çavkaniyê.

2. Struktura Derveya Bushings

Komponentên derveya bushing-ê girîng in: terminal boards, lead connectors, rain covers, oil level gauges, oil plugs, oil reservoirs, upper porcelain sleeves, lower shields, lifting rings, oil valves, nameplates, vent plugs, connecting bushings, lower porcelain sleeves, û equalizing balls.

3. Struktura Navendeka Bushings

• Struktura Îsolan Sereke: Ji nîvekên capacitor core cihazkirin, ku ji cable paper û aluminum foil equalizing electrodes hatine çêkirin; îsolan derveya ji porcelaine sleeves çêkirin, ku wekî containeran ji bo transformer oil da.

• Performansa Îsolan: Ji struktura full sealed çêkirin, ku transformer oil navendekan wekî sistem independent ne û li ser şertên atmosfera derveyî ne.

• Metoda Connexion: Li ser spring mechanical fastening zorî çêkirin, ku performansa îsolan û kompensasyona dilandin/gotinan li ser guherandina termal.

Oil reservoir li sera bushing-ê bi karîna şangawana oil volume li ser guherandina termal, ev dikare ku biguhere malpera navendekan; oil level gauge li ser oil reservoir dikare ku real-time monitor bike oil level. Equalizing ball li sera navenda bushing-ê electric field distribution bêrîne, ku herî lêz dijîne îsolan navendekan û komponentên grounded an coils.

Bushing beşek li ser end screen ya oil-paper capacitor bushings bikar îst bi testên capacitance, dielectric loss factor, û partial discharge tests ya transformers. Dema xebitandina normal, bushing beşek divê li ser ground reliable bikar îst. Eger ku li ser disassembling bushing beşek ya end screen, dê werdibûne ku hêviya rotation an pulling out li ser bushing rod, ji bo wê ku navendekan disconnection an damage li ser copper foil ya electrode plate.

4. Arrangement of Three-Phase Transformer Bushings

Ji ber rastîna high-voltage bushing side ya transformer, arrangement li ser left-to-right bêje:

• High voltage side: O, A, B, C

• Medium voltage side: Om, Am, Bm, Cm

• Low voltage side: O, a, b, c

5. Classification of Bushings by Insulation Material and Structure

Bushings din divide into three categories:

• Single Insulation Bushings: Including pure porcelain bushings and resin bushings;

• Composite Insulation Bushings: Further divided into oil-filled, gel-filled, and gas-filled bushings;

• Capacitor Bushings: Including oil-paper capacitor bushings and resin-paper capacitor bushings.

6. Oil-Paper Capacitor Bushings

According to the current-carrying structure, oil-paper capacitor bushings can be divided into cable-through type and conduit current-carrying type. Among them, the conduit current-carrying type is further classified into direct-connection type and rod-through type based on the connection method between the oil-side terminal and the bushing. Cable-through and direct-connection conduit current-carrying bushings are widely used in power systems, while rod-through oil-paper capacitor bushings are less common.

The manufacturing process of the capacitor core for capacitor bushings is as follows: Starting with a hollow conductive copper tube as the base, a layer of cable paper with a thickness of 0.08-0.12mm is first tightly wrapped as the insulation layer, followed by a layer of aluminum foil with a thickness of 0.01mm or 0.007mm as the capacitor shield; this alternating wrapping of cable paper and aluminum foil is repeated until the required number of layers and thickness are achieved.

This forms a multi-layer series capacitor circuit—where the conductive tube is at the highest potential, and the outermost aluminum foil is grounded (ground shield). According to the principle of series capacitor voltage division, the voltage between the conductive tube and the ground equals the sum of the voltages between each capacitor shield layer, and the voltage between shield layers is inversely proportional to their capacitance. This ensures that the total voltage is evenly distributed across the entire insulation layer of the capacitor core, achieving a compact and lightweight design for the bushing.