low-loss

1.Product Introduction 

The 35kV S18 Series Oil-Immersed Power Transformer represents a next-generation high-efficiency, low-loss energy-saving transformer that complies with China's latest energy efficiency standards. As a flagship product in the mid-to-high-end energy-saving segment for 35kV voltage levels, it features high-permeability low-loss silicon steel sheets, optimized magnetic circuit design, and fully sealed corrosion-resistant construction. With advantages including reduced energy losses, lower noise levels, enhanced operational stability, and extended service life, this transformer is widely deployed in 35kV power transmission and distribution systems. Ideal for grid construction projects, energy-saving retrofits, industrial power supply applications, and renewable energy integration scenarios, it stands as the preferred solution for energy conservation and sustainable power generation.

2. Technical Specifications（customizable）

 • Rated Voltage: 35kV±2×2.5% / 10kV / 0.4kV • Rated Frequency: 50Hz • Connection Group: YNd11, Dyn11 • Cooling Method: ONAN oil-immersed self-cooling • Rated Capacity: 50kVA to 31,500kVA • Impedance Voltage: 6.5%–8% (capacity-dependent) • Insulation Class: Class A • Protective Structure: Fully sealed corrugated oil tank with plate-type radiator • Operating Environment Temperature: -30°C to +40°C

 3. Key Features 

1. High Energy Efficiency with Minimal Losses The no-load and load losses significantly outperform S11 and S13 series, delivering exceptional energy savings. Long-term operation reduces electricity costs substantially while ensuring rapid return on investment.

Ultra-low noise and environmental friendliness: The iron core employs multi-stage joints and vibration damping technology, ensuring uniform magnetic circuit distribution and low operational noise, making it suitable for high-quietness environments such as residential areas, schools, and hospitals.

Fully sealed structure with maintenance-free operation: The oil-free full-seal design isolates transformer oil from air, effectively preventing oxidation, moisture absorption, and leakage, thereby eliminating the need for core lifting and routine maintenance.

Superior short-circuit resistance: The windings feature a high-strength structural design with stable insulation performance and high mechanical strength, effectively resisting grid surges, load fluctuations, and short-circuit faults.

Excellent heat dissipation performance with stable operation. The optimized heat dissipation structure ensures low temperature rise, enabling long-term full-load operation. The equipment exhibits high reliability and low failure rate.

Long service life and strong adaptability: The oil tank features corrosion-resistant and weather-resistant properties, with an overall design that ensures extended service life. It can withstand various complex environments including outdoor settings, high-altitude areas, humid conditions, dusty environments, and coastal regions.

4. Application Scenarios

 • New construction, upgrading, and energy-efficient retrofitting of urban/rural 35kV power grids • Main power supply for large factories, mines, metallurgical plants, chemical facilities, and industrial parks • Step-up power supply solutions for wind farms, photovoltaic plants, and energy storage stations • Power supply for hospitals, schools, commercial centers, high-end residences, and office buildings • Infrastructure projects including water conservancy systems, railways, highways, municipal facilities, and airports • Power supply for main transformers in substations, containerized substations, and outdoor tower-mounted power distribution systems