Cast Resin Transformer

  1. Product Overview We adopt optimized CAD design for cast resin dry type transformer with advanced technologysoftware from Europe in 1994. The core is made of cold-rolled grain-oriented silicon steel sheet cut in step-lap by automatic cutting line from GEORG,Germany and laminted with method of fifth-order step-by step stack technology. In this way, no-load performance of the core is greatly improved. The winding assembly is casted in the vaccum resin casting machine imported from Hedrich, Germany. The resin material are provided by (HUNTSMAN)CIBA-GEIGY, Switzerland. All these equipment and material ensure good permeability, no bubbles of casted resin, which leads to minimum partial discharge and high capability to withstand short circuit and vibration. Under normal service condition, the service life of dry type transformer is 30years. No crackle will form on the surface of transformer winding due to temperature variation as long as the transformer runs under normal service condition. 2. Product Characteristic Low-noise low-loss 1) The core is made of high quality cold-rolled grain-oriented silicon-steel sheet. The lamination sheets are produced by automatic step-lap core lamination line from GEORG, Germany. Such method improves the distribution of magnetic circuit result in lowering the noise level. 2) Product design adopts CAD software. By selection of high- quality silicon steel sheet and applying lower fluxdensity, noise and no-load loss are reduced due to lower the harmonious in the core. 3) All parts used for clampig apply silicone rubber and flexible elements as buffers in order to reduce the amplitude and noise of components, while the surface of core is coated is coated with a certain thickness of resin, which plays a role of sound-proof. 3. Non-flammed, no pollution to environment 1) Solid electrical insulation composed of high quality resin and glass fibre could provide with high electrical strength(breakdown voltage≥34V/MM) and partial discharge can be controlled in the range of  ≤5PC. 2) As resin and glass fibre composite materials used in dry-type transformer generate very little heat when in combustion( about 65mj/kg), the transformer has characteristic of fibre-retardant self- extinguishing. 3) Dry-type transformer core is coated with resin, while the coil is all encapsulated by resin. The transformer can provide relative reliable operation in circumstance of 100% humidity, and has high anti-corrosion ability. Dry-type transformer also has good advantages such as strong overload capability, good thermal stability, compact size, light weight, easy to install, maitenance-free and so on. Dry-type transformer is widely used in high- rise buildings, commercial centers, airports, stations, ports, subway, factories and underground power distribution stations. 4. Core The core is made of high quality cold-rolled grainoriented silicon-steel sheet, laminated by automatic step-lap core lamination line imported from GEORG, Germany. Such method improves the distribution of magnetic circuit result in lowering the noise level. By selection of high-quality silicon steel sheet and applying advanced technology, equipment, no-load performance of transformer is improved. Compared with conventional core, no-load loss, no-load current and noise level are reduced by 5%-6%, 20%-30%, 6% respectively. 5. Coil Cast-resin high-voltage coil High-voltage coil applies fraction-layer structure, casted with Huntsman( the former Swiss CIBA) resin materals, Germany) and by HEDRICH vacuum casting equipment. Low-voltage coil applies foil structure. Advanced technology ensures little partial discharge of coil and strong ability to withstand short circuit. 6. Tapping range of high-voltage coil Un ± 5% and Un ± 2x 2.5% OCTC, as well as Un ± 4 x 2.5% OLTC. Temperature control device With fault alarm, over-temperature alarm, over-temperature tripping, three-phase polling.