SFS11 Series Transformer Product Details

1. Product Introduction

The SFS11 series is a three-phase, three-winding, oil-immersed air-cooled power transformer designed for 35kV/110kV high-voltage systems. Developed on the 11-type ultra-low loss technology platform, its key advantage lies in realizing power distribution and voltage conversion for high-voltage, medium-voltage and low-voltage circuits with a single unit.

It is specially designed for main network power supply scenarios such as regional power grids, large industrial and mining enterprises, and new energy booster stations. While ensuring power supply reliability and voltage stability, the product achieves low operation loss, strong impact resistance and long maintenance-free service life through optimized energy efficiency and structural design. It is the mainstream choice for replacing old main transformers and constructing new substations.

2.1 Rated Parameters

• Rated Capacity: 3150kVA ~ 63000kVA

• Rated Voltage: High voltage 110kV; Medium/Low voltage 35kV/10kV (customizable)

• Rated Frequency: 50Hz

• Connection Group Symbol: YNd11y10 (standard, customizable)

2.2 Voltage Regulation

• Regulation Mode: On-load tap changer installed on the high-voltage side

• Regulation Range: ±3×2.5%

• Function: Realizes uninterrupted and precise voltage regulation to ensure stable voltage quality under various loads

2.3 Performance Index

• Energy Efficiency: Complies with Class 1 energy efficiency standard of GB/T 10228-2015

• No-load Loss: Reduced by about 30% compared with the traditional S9 series

• Noise Level: Low-noise design, meeting strict industrial environmental limits

• Cooling Mode: ONAN/ONAF (Oil Natural Air Natural / Oil Natural Air Forced), switchable

3. Main Features

3.1 Three-Winding Integration for Higher Efficiency

Adopting a three-winding structure, it realizes power transmission and distribution among high, medium and low voltages without parallel connection of multiple transformers. A single unit completes hierarchical power supply for regional power grids, greatly simplifying substation wiring, saving land occupation and investment. The flexible capacity allocation adapts to complex power supply topologies.

3.2 Ultra-Energy-Saving for Lower Life-Cycle Cost

The core adopts high-permeability cold-rolled silicon steel sheet with precision lamination technology, greatly reducing no-load loss. The winding uses high-purity oxygen-free copper conductor to effectively reduce load heating and loss. Compared with old models, the annual comprehensive power consumption is significantly reduced, with a short investment payback period.

3.3 High Reliability & Strong Short-Circuit Withstand Capacity

Designed for short-circuit resistance, the winding adopts ampere-turn balance technology and reinforced end insulation, together with high-strength core frame and unique compression structure. It can effectively withstand impact electromotive force caused by sudden short circuits, with extremely low failure rate, suitable for high-reliability operation of the main network.

3.4 Air Cooling for Stable Operation

With oil-immersed air-cooled (ONAF) design and high-efficiency radiator system, the unit can dissipate heat rapidly by activating the forced air cooling system during peak load. It supports an overload capacity of more than 20% of the rated capacity, coping smoothly with load fluctuations, low temperature rise, slow insulation aging and long service life.

3.5 Fully Sealed & Maintenance-Free

Adopting fully sealed corrugated oil tank or capsule-type oil conservator structure, the transformer is completely isolated from air, preventing transformer oil oxidation, moisture absorption and degradation. It features a long maintenance-free period, good outdoor environmental tolerance, anti-corrosion and anti-rust properties, suitable for long-term outdoor application.

4. Applications

1. Regional Power Grids & Substations: Used as main transformers in 110kV/35kV substations, serving as power supply hubs for urban or large regional power grids.

2. Large Industrial & Mining Enterprises: Applied in main substations of steel, petrochemical and energy bases to provide stable and flexible power for multiple high and low voltage production lines.

3. New Energy Power Stations: Used in booster stations of wind farms and photovoltaic power stations to efficiently collect new energy power and stably transmit it to the main grid.

4. Parks & Infrastructure: Serving key infrastructure projects such as large industrial parks, airports and data centers with high requirements for power capacity and reliability.