630 kva Three Phase Dry Type Transformer

This 630 kVA three-phase dry-type transformer from SGOB features 100% copper windings, 5000V high voltage, and 50Hz/60Hz frequency. It complies with IEC standards for use in power plants, substations, etc. Rated voltages include 6kV, 6.3kV, 10kV, 10.5kV, and 11kV.  Customization for specific requirements is available. Please contact us for more details.

Product Features:

1. The coils use copper conductors with fiberglass composite insulation, vacuum-cast in epoxy resin for a bubble-free, sealed structure. 

2. The core uses grain-oriented silicon steel sheets with a stepped-lap design to reduce hysteresis loss. 

3. The low-voltage side uses a foil winding structure with automatic argon arc welding for uniform current distribution.

4. An intelligent temperature control system with an axial fan regulates cooling efficiency. 

5. The stamped casing features cooling fins for enhanced convection, and a corrosion-resistant coating protects against salt spray.  

Production Process: 

After winding, the copper wire is pre-impregnated with insulating varnish, then vacuum-cast in epoxy resin for curing. The core is laser-cut and stacked, with hydraulic clamps applying constant pressure. After assembly, the core and coils are baked to bond the components. Partial discharge scanning and harmonic analysis are performed before shipment, with data uploaded to the cloud for traceability.

Key Advantages over Oil-Immersed Transformers:

1. Oil-immersed transformers have a risk of oil leakage due to seal failure, potentially causing soil pollution and fire hazards; the 630 kVA three-phase dry-type transformer eliminates flammable media, and the resin self-extinguishes in case of an arc fault, preventing secondary damage. Oil-immersed transformers generate flammable gases under overload conditions, requiring gas protection systems. Dry-type transformers directly monitor the temperature of the hottest point using embedded sensors, improving the speed of early warning and response. 

2. In oil-immersed transformers, changes in oil viscosity at low temperatures affect heat dissipation efficiency, and high temperatures accelerate insulation aging; the thermal expansion coefficient of the epoxy resin in dry-type transformers matches that of copper conductors, maintaining mechanical stability under extreme temperature variations. Oil-immersed transformers require periodic oil quality and moisture content testing; the fully sealed structure of dry-type transformers allows operation in 100% humidity environments, eliminating the need for additional protective enclosures in marine environments with salt spray corrosion. 

3. Oil-immersed transformer maintenance requires specialized oil filtration equipment and waste oil disposal costs; accidental leaks result in site cleanup costs; dry-type transformers only require compressed air cleaning for surface dust accumulation, with no consumable replacement costs. Disposal of oil-immersed transformers involves hazardous waste procedures; dry-type materials can be mechanically crushed, sorted, and recycled, significantly increasing residual value. Oil-immersed transformer repairs require oil draining procedures; dry-type transformers support modular winding replacement, reducing downtime.

Maintenance Notes

1. Do not use a high-pressure air gun directly on the heat sink during operation of a 630 kVA three-phase dry-type transformer to avoid micro-cracks in the resin.

2. Clean dust from the heat dissipation channels with a soft brush if accumulated for more than three months.

3. Check for salt crystal formation on the terminals in coastal areas before the monsoon season.

4. Perform inter-turn insulation testing after a sudden short circuit.

5. Seal and store in a dry environment during long-term storage; maintain a constant temperature and humidity for 48 hours before restarting.

Is the overload capacity lower than that of oil-immersed transformers?

The resin-encapsulated windings have a higher thermal capacity, and under forced air cooling, the continuous overload time is actually longer than that of oil-immersed transformers; the insulation recovery speed after a sudden short circuit is also faster.

Product Parameters