10KV S11 Oil Immersed Transformer 50-5000KVA

1. Overview

S11 series 10kV oil immersed distribution transformer is a widely used energy-efficient power transformer conforming to IEC60076 and GB/T1094 standards, covering capacities from 50kVA to 5000kVA. Standard voltage ratio: 10±2×2.5%kV / 0.4kV, connection group Dyn11 as default. It is a cost-effective upgrade replacing old S9 transformers with obviously reduced no-load loss and running consumption, extensively used in urban & rural power grid renovation, industrial plants, mines, commercial buildings, residential districts and new energy power distribution projects for domestic and overseas power engineering.

2. Main Structure Features

Core

Fabricated from high-quality grain-oriented cold rolled silicon steel sheet with full miter lap cutting technology, which minimizes magnetic leakage flux and no-load loss. Non-magnetic clamping structure avoids local overheating and effectively reduces operating noise.

HV & LV Windings

Made of high-purity oxygen-free copper wire with compact regular winding structure. All windings go through strict vacuum drying and full vacuum oil filling to eliminate internal air bubbles, enhancing insulation performance and strong short-circuit withstand capability against sudden grid short-circuit impact. Off-circuit tap changer on high voltage side realizes ±2×2.5% voltage adjustment to adapt unstable incoming grid voltage.

Oil Tank & Cooling System

Adopts fully welded corrugated steel tank, standard cooling mode ONAN (natural oil & natural air cooling); ONAF forced air cooling is optional for transformers above 2500kVA to improve overload capacity. Outer surface coated with anti-corrosion paint, suitable for outdoor installation under humid, dusty and coastal salt-fog environment. Insulating oil serves as both cooling medium and insulating medium.

Standard Fittings

Equipped with gas relay, oil level indicator, pressure relief valve, drain valve and temperature measuring parts for real-time operational monitoring; on-load tap changer and remote temperature display module can be customized as required.

3. Product Advantages

Good Energy Saving: Lower no-load loss and no-load current than S9 model, cutting long-term power operation cost for end users.

High Operational Stability: Optimized mechanical structure of windings and core enables long-term continuous full-load operation, strong anti-short-circuit performance.

Low Noise: Precision assembly plus shock absorption design keeps running noise within national standard limits, fit for residential area and downtown substations.

Strong Customization: Complete capacity range from 50kVA to 5000kVA; special secondary voltage, impedance and connection group can be customized per customer’s technical drawing.

Low Maintenance: Standardized spare part layout, convenient for routine oil test and daily inspection, low after-sale maintenance cost.

4. Application Range

Urban & county 10kV distribution network and rural power grid upgrading

Factories, metallurgy, chemical plants and mining enterprise power transformation

PV power station, wind farm 10kV distribution system

Shopping malls, residential communities, data centers and transportation supporting power supply

Overseas power grid construction and international EPC bidding projects

5. Quality Assurance

Each transformer undergoes complete factory tests including temperature rise test, dielectric withstand test, short-circuit withstand test and partial discharge test, with full test reports and relevant certifications available for export clearance.