a step up transformer

1.Product Introduction 

The 35kV S22 Series Oil-Immersed Power Transformer is an ultra-high energy efficiency product developed in compliance with China's GB 20052-2024 Class I Energy Efficiency Standard, currently representing the top-tier transformer in energy efficiency for 35kV voltage levels. Featuring ultra-high magnetic permeability low-loss cold-rolled oriented silicon steel sheets, oxygen-free copper windings, optimized magnetic circuit design, and fully sealed corrosion-resistant heat dissipation systems, this product delivers comprehensive upgrades in loss control, operational noise reduction, mechanical strength, and service life. It serves as a core energy-saving power supply solution for high-end applications including grid upgrades, renewable energy integration, industrial power supply, data centers, and urban infrastructure projects.

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% • Insulation Class: Grade A • Protection Type: Fully sealed corrugated oil tank with plate-type radiator • Operating Environment: -30°C to +40°C, adaptable to outdoor, plateau, coastal, high-humidity, and high-salt fog environments

 3. Key Features 

1. Tier 1 energy efficiency with ultra-low losses: Null-load and load losses significantly outperform models like S20, S18, and S13, delivering exceptional energy savings. Long-term operation substantially reduces electricity costs, aligning with China's dual-carbon policy and energy-saving retrofit requirements.

Ultra-low noise and environmental friendliness: Utilizing multi-stage jointed iron cores and vibration-damping structures, the operating noise level significantly exceeds national standards, making it suitable for high-quietness environments such as hospitals, schools, residential areas, and office buildings.

Fully sealed structure with maintenance-free oil-free bearing design. Vacuum oil injection technology ensures insulation oil remains isolated from air, providing oxidation resistance, moisture protection, and leak prevention. This eliminates core lifting requirements and daily maintenance, resulting in extremely low operational and maintenance costs.

Strong short-circuit resistance and high reliability, with high mechanical strength of windings and stable insulation structure, capable of withstanding grid surges, load fluctuations, and short-circuit stresses, ensuring safe and stable operation with low failure rates.

Lower temperature rise and extended service life: Optimized heat dissipation design ensures excellent temperature rise control, effectively delaying insulation aging. The equipment can operate stably at full load for prolonged periods, resulting in longer service life.

Strong environmental adaptability: The oil tank features corrosion-resistant and weather-resistant properties, enabling long-term reliable operation in complex environments such as outdoor substations, container substations, mountainous areas, coastal regions, and high-altitude areas.

4. Application Scenarios

 • New construction and energy-efficient retrofitting of 35kV backbone power grids for State Grid and China Southern Power Grid • Step-up transformers for wind power plants, photovoltaic power stations, and energy storage facilities • High-load power supply solutions for data centers, IDC facilities, industrial parks, high-end manufacturing plants, mining operations, metallurgical plants, and chemical plants • Public buildings including hospitals, schools, commercial complexes, luxury residences, and office towers • Large-scale infrastructure projects such as railways, airports, highways, water conservancy projects, and municipal facilities • Compact urban substations, containerized substations, and outdoor tower-based power supply systems