500kV 550kV Single-phase Oil-Immersed Air-Cooled Autotransformer with Three Windings and No Excitation

Description：

As a pioneer in China's power transformer industry, we have specialized in the R&D and manufacturing of power transformer equipment for decades, and established industry standards with core technologies.

The 500kV/550kV Single-Phase Oil-Immersed Air-Cooled Autotransformer with Three Windings and No Excitation is engineered for ultra-high voltage transmission networks requiring exceptional reliability and efficiency. Its oil-immersed air-cooled (ONAN) design ensures effective heat dissipation under continuous operation, while the three-winding configuration provides flexible power allocation and system interconnection capabilities. The no-excitation voltage regulation mechanism eliminates the complexity of on-load tap changers, reducing maintenance needs and enhancing operational stability. Ideal for core grid substations, this transformer delivers robust performance in demanding environments with minimal lifecycle costs.

This power transformer is fully compliant with international standards including IEC 60076-1, IEEE C57.12.00, ANSI C57.12.90, AS/NZS 60076.5 and EN 61558-1. It meets quality requirements and is widely adaptable to the operational needs of power grids in multiple overseas regions.

Product Characteristics:

• Rational Structural Design：Leveraging advanced modern calculation technologies, the transformer’s structure is optimized through in-depth analysis of its electrical, magnetic, mechanical, and thermal properties. This ensures structural integrity and performance synergy across all operational conditions.

• Advanced Performance Indicators：Compliant with international IEC standards, the product can also be tailor-made to meet specific customer requirements. Its partial discharge (PD) level is significantly lower than the limit specified in IEC 60076-3, delivering exceptional electrical performance and operational stability.

• High Operational Reliability：Reliability is guaranteed by comprehensive analysis of electrical, magnetic, mechanical, and thermal characteristics. Combined with a scientific insulation structure, optimized ampere-turn distribution, and efficient cooling system, it boasts strong resistance to overvoltage and short-circuit currents, eliminating the risk of local overheating during long-term operation.

• Premium Configured Accessories：Equipped with high-quality accessories, the transformer offers superior user experience. It features an aesthetically pleasing appearance, reliable leak-proof design, and supports maintenance without tank disassembly—achieving a near maintenance-free operation mode that reduces operational costs and workload.

Technical Parameters:

The voltage classes of some of these Power Transformer include 6kV, 6.3kV, 6.6kV, 6.9kV, 7.2kV, 10kV, 10.5kV, 11kV, 11.5kV, 12kV, 13.2kV, 13.8kV, 14.5kV, 14.4kV, 15kV, 15.5kV, 15.6kV, 17.5kV, 20kV, 21.9kV, 22kV, 24kV, 30kV, 33kV, 33.5kV, 34.5kV, 35kV, 36kV, 38kV, 38.5kV, 40.5kV, 44kV, 45kV, 46kV, 66kV  69kV.72.5kV 88kV 110kV 115kV 123kV 125kV 126kV 132kV 138kV 145kV 150kV 154kV 161kV 170kV  220kV 225kV 230kV 245kV 275kV 330kV 345kV 363kV 380kV 400kV 500kV Power transformers of voltage ，and aboveand customization is available.

Among these, some autotransformers cover non-standard voltage levels including 121kV, 132kV, 138kV, 200kV, 225kV, 230kV, 245kV, 275kV, 330kV, 345kV, 400kV and 756kV, We also provide customization services.

500kV 100MVA~484MVA Single-phase, Double-winding Power Transformer with Off-circuit Tap-changer

Note: Transformers with various special parameters and performance can be manufactured according to customer requirements.

500kV 120MVA~1170MVA Three-phase, Double-winding Power Transformer with Off-circuit Tap-changer

Note: Transformers with various special parameters and performance can be manufactured according to customer requirements.

500kV 120MVA~1170MVA Three-phase, Double-winding Power Transformer with Off-circuit Tap-changer

Note: Transformers with various special parameters and performance can be manufactured according to customer requirements.

Normal Service Conditions

(1) Altitude:  ≤1000m;

(2) Ambient temperature:Maximum temperature: +40℃;Maximum monthly average temperature: +30℃;Maximum yearly average temperature: +20℃;Minimum temperature: -25℃.

(3) Power supply: approximate sinusoidal wave, three-phase symmetrical approximately

(4) Installation site: indoor or outdoor, without the obvious contamination.Note: The transformer used in special conditions should be specified when ordered.