Oil-Immersed Power Transformer 5MVA–30MVA up to 220kV IEC 60076 Manufacturer
Product Overview
TNNPI oil-immersed power transformers are engineered for transmission substations, industrial power systems, renewable energy integration, and utility grid expansion. Covering ratings from 5MVA to 30MVA with voltage classes up to 220kV, these transformers provide outstanding operational reliability, low lifecycle costs, and stable performance under continuous heavy loads.
Advanced Magnetic Circuit Design
The transformer utilizes high-grade grain-oriented silicon steel with optimized step-lap core construction to reduce magnetic losses and improve operating efficiency. Precision engineering ensures excellent voltage regulation and reduced operating noise.
- High operating efficiency
- Low excitation current
- Reduced no-load losses
- Excellent voltage stability
Heavy-Duty Winding System
Windings are manufactured using oxygen-free copper or high-conductivity aluminum conductors with reinforced insulation systems designed for high short-circuit withstand capability. Vacuum drying and oil treatment enhance dielectric performance and extend service life.
- Superior thermal performance
- High short-circuit strength
- Stable operation under heavy load
- Long insulation lifespan
Designed for Large-Scale Power Networks
Available with multiple cooling methods, tap changers, and protection accessories, each transformer can be configured for transmission substations, industrial plants, renewable energy stations, and national grid projects.
- Voltage up to 220kV
- Capacity from 5MVA to 30MVA
- ONAN / ONAF / OFAF optional
- OLTC or NLTC available
- IEC, ANSI, IEEE compliant
Comprehensive Factory Testing
Every transformer undergoes strict electrical and mechanical testing before delivery, ensuring reliable operation throughout its service life. Additional witness testing can be arranged according to customer requirements.
- Routine and type tests available
- Partial discharge testing optional
- Temperature rise testing
- Lightning impulse testing available
- Factory Acceptance Test (FAT) supported
Typical Applications
- Power transmission substations
- Utility grid expansion
- Renewable energy plants
- Large industrial facilities
- Mining operations
- Steel mills
- Petrochemical plants
- Urban infrastructure
General Technical Parameters
| Item | Specification |
|---|---|
| Rated Capacity | 5–30MVA |
| Highest Voltage | Up to 220kV |
| Frequency | 50Hz / 60Hz |
| Phase | Three Phase |
| Cooling Method | ONAN / ONAF / OFAF |
| Tap Changer | OLTC / NLTC |
| Winding Material | Copper / Aluminum |
| Insulation Class | Mineral Oil / FR3 Optional |
| Standards | IEC 60076, ANSI/IEEE C57 |
| Service Life | ≥30 Years (Proper Maintenance) |
Get in Touch
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