¿Qué es un transformador sumergido en aceite??

¿Qué es un transformador sumergido en aceite??

Untransformador sumergido en aceite is a power transformer that usesaceite aislante (aceite mineral o éster sintético) for bothenfriamiento yaislamiento eléctrico. El núcleo y los devanados están sumergidos en aceite., which dissipates heat and prevents electrical breakdown.

Key Components

1. Centro: Laminated silicon steel to reduce eddy current losses.

2. Devanados: Copper or aluminum conductors (HV/LV).

3. Tanque: Sealed steel container filled with oil.

4. Insulating Oil:

• Mineral oil (most common).

• Bio-based or synthetic ester (eco-friendly alternatives).

5. Cooling System:

• Radiators/fins (ONAN – Oil Natural Air Natural).

• Fans (ONAF – Oil Natural Air Forced).

6. Protection Devices:

• Relevo Buchholz (gas detection for internal faults).

• Pressure relief valve.

• Sensores de temperatura (oil/winding).

Types of Oil-Immersed Transformers

1. Hermetically Sealed

• Fully sealed tank (no oil exposure to air).

• No conservator; bajo mantenimiento.

2. Conservator-Type

• Expansion tank (conservador) with breather to absorb moisture.

• Common in large transformers.

3. Step-Lap Core Design

• Reduced no-load losses and noise.

4. Specialty Types:

• Fire-resistant (less-flammable oil).

• Underground (diseño compacto).

Ventajas

✔ Alta eficiencia: Oil provides excellent heat dissipation.
✔ Long Lifespan: Correctamente mantenido, lasts 25-30 años.
✔ Rentable: Lower initial cost than dry-type transformers.
✔ Capacidad de sobrecarga: Handles temporary overloads better.

Desventajas

✖ Fire Risk: Oil is flammable (requires fireproof barriers).
✖ Mantenimiento: Regular oil testing and leak checks needed.
✖ Preocupaciones ambientales: Oil disposal and spill risks.

Aplicaciones

• Power Distribution: Step-down 11kV/33kV to 400V.

• Industrial Plants: acerías, chemical factories.

• Energía Renovable: Wind/solar farm substations.

• Railways: Traction power supply.

Maintenance Requirements

1. Oil Testing:

• Dielectric strength (>30 kV for mineral oil).

• Acidity (<0.1 mg KOH/g).

• Moisture content (<20 ppm).

2. Leak Inspection: Check gaskets, welds, and valves.

3. Sludge Removal: Clean oil ducts periodically.

Estándares & Certificaciones

• CEI 60076: Estándares internacionales.

• IEEE C57.12.00: North American standards.

• GB/T 6451: Chinese standards.

Oil-Immersed vs. Transformadores de tipo seco

Purchasing Considerations

1. Capacidad (kVA): Match to load requirements.

2. Relación de voltaje: Input/output voltage levels.

3. Impedancia: Typically 4–10% for distribution transformers.

4. Environment: Indoor/outdoor, temperatura, humedad.

5. Certificaciones: Ensure compliance with local regulations.

Preguntas frecuentes

q: Can oil-immersed transformers be used indoors?
A: Sí, but require fireproof vaults and ventilation (NFPA 70 normas).

q: How often should oil be tested?
A: Annually for routine checks; after overloads or faults.

q: Are biodegradable oils reliable?
A: Sí, synthetic esters offer similar performance with lower fire risk.

For acustomized selection, proporcionar:

• Load details (kVA, Voltaje).

• Entorno de instalación.

• Special requirements (p.ej., bajo ruido, high efficiency).