Proveedor de componentes electrónicos | Transformadores, Inductores, Inversores
Trafo (Transformador) – Comprehensive Guide
1. Main Types of Trafo
(1) By Cooling Method
Oil-Immersed Trafo
Uses insulating oil for cooling, suitable for high-voltage and high-capacity applications (p.ej., grid substations).
Common Models: ONÁN (natural cooling), ENCENDIDO APAGADO (forced air cooling), OFAF (forced oil and air cooling).
Dry-Type Trafo
Oil-free design, insulated by air or resin, ideal for fire-sensitive environments (p.ej., hospitales, centros de datos).
Common Models: SCB (epoxy resin-cast), SG (open-type).
(2) By Application
Distribution Trafo
Niveles de voltaje: 10kV/0.4kV, used for end-user power supply (p.ej., residential areas, fábricas).
Power Trafo
Voltage levels ≥110kV, used in transmission networks (p.ej., substation main transformers).
Special Trafo
Includes rectifier transformers (for electrolysis), mining transformers (explosion-proof design), etc..
2. Especificaciones clave
| Parámetro | Descripción |
|---|---|
| Capacidad nominal | p.ej., 100kVA, 5000kVA; must be calculated based on load. |
| Relación de voltaje | Input/output voltage (p.ej., 10kV/0.4kV). |
| Voltaje de impedancia | Typically 4%~10%, affects short-circuit current. |
| Connection Group | p.ej., Dyn11 (common for distribution), Yyn0 (balanced low-voltage loads). |
| Método de enfriamiento | ONÁN, ENCENDIDO APAGADO, OFWF (oil-immersed); ENCENDIDO/APAGADO (tipo seco). |
| Efficiency Class | Chinese standard (ES 20052): Clase 1 (highest efficiency), Clase 2, Clase 3. |
3. Applications
Power Systems: Voltage step-up/down, grid interconnection.
Industrial: Power supply for motors, hornos (custom impedance may be required).
Renewable Energy: PV/wind grid integration (must withstand harmonics).
Rail Transit: Traction transformers (25kV/50Hz).
4. Selection Guide
Indoor Installation: Prefer dry-type (fireproof) or fully sealed oil-immersed.
Outdoor Installation: Oil-immersed (protection class ≥IP55).
High Load Fluctuations: Choose models with strong overload capacity (p.ej., ONAF cooling).

5. Preguntas frecuentes
Q: How to choose between oil-immersed and dry-type transformers?
A: Oil-immersed offers lower cost and higher capacity but requires fire protection; dry-type is safer for confined spaces.
Q: How to calculate required capacity?
A: Sum all load power (kVA) and reserve 20%~30% margin.
Q: How to reduce transformer noise?
A: Select low-noise designs (p.ej., step-lap core) or install soundproof enclosures.








