high voltage transformer

1.Product Introduction: 

The 35kV S9 Series Oil-Immersed Transformer is a classic high-voltage distribution equipment developed in China using traditional high-quality manufacturing processes. Featuring premium cold-rolled oriented silicon steel sheets, high-conductivity oxygen-free copper conductors, and advanced core structures, this product demonstrates outstanding advantages in the 35kV voltage range, including mature technology, stable operation, and excellent cost-performance ratio.

This product can stably achieve electrical energy conversion and distribution ranging from 35kV to 10kV/0.4kV, and is widely applied in regional main power grids, industrial and mining enterprises, as well as large-scale infrastructure projects. It serves as a standard mainstream distribution equipment that balances reliability and economic efficiency.

2. Technical Specifications （customizable）

Core Rated Parameters • Rated Voltage: High-voltage side 35kV (±5% tap adjustment), low-voltage side 10kV/0.4kV (three-phase four-wire system) • Rated Frequency: 50Hz • Connection Group: Commonly used Dyn11 • Cooling Method: ONAN (oil-immersed self-cooling) Loss and Performance Parameters • Capacity Range: 30kVA to 6300kVA (common specifications: 50,100,200,315,400,500,630,800,1000,1250,1600,2000,2500,3150,4000,5000,6300kVA) • Impedance Voltage: 4% or 6.3% (adjustable with capacity) • Insulation Class: Grade A • Noise Level: ≤65dB (slightly fluctuates with capacity) • Operating Temperature: Top oil temperature rise ≤55K, maximum top oil temperature not exceeding 95°C Environmental Protection • Operating Environment: -30℃ to +40℃, adaptable to high humidity and dusty outdoor conditions • Protective Structure: Fully sealed oil tank or storage cabinet with anti-corrosion coating 

3. Key Features 

1. Mature Technology and Universal Compatibility The S9 series has undergone extensive market validation, featuring standardized manufacturing processes and high component compatibility. With extremely low equipment failure rates, it represents one of the lowest-risk equipment options for 35kV power grid construction and retrofitting, meeting diverse conventional power supply requirements.

Stable performance with reliable impact resistance: The iron core employs a multi-stage laminating process for uniform magnetic circuit distribution; the coil utilizes high-strength conductors combined with a longitudinal oil channel structure to ensure high mechanical strength. It demonstrates excellent resistance to sudden short circuits, effectively addressing complex operating conditions such as grid voltage fluctuations and load surges, thereby ensuring long-term stable operation.

Moderate energy loss with high cost-effectiveness Compared to earlier outdated models, the S9 series optimizes silicon steel sheet selection and magnetic circuit design, keeping both no-load and load losses within reasonable ranges. While maintaining core performance, it offers competitive manufacturing costs, making it particularly suitable for large-scale power grid deployment or projects with limited budgets, delivering high ROI through cost-effective solutions.

Fully sealed structure with convenient maintenance: The fully sealed corrugated oil tank or oil storage cabinet design effectively prevents oxidation, moisture absorption, and leakage of insulating oil. Routine maintenance is simple, requiring only periodic inspection of oil level and temperature without frequent core-lifting repairs, significantly reducing lifecycle operational and maintenance costs.

Broad adaptability and excellent weather resistance: The fuel tank is coated with anti-corrosion paint, featuring a robust overall structure that can withstand harsh outdoor environments such as intense sunlight, humidity, and significant temperature fluctuations. It ensures safe and stable operation in both high-altitude regions and coastal humid areas.

4.Application Scenarios 

1. Regional backbone power grid adaptation: Designed for 35kV county-level power grids and township power supply trunk lines, this core equipment connects regional power sources with end-user loads, ensuring reliable and stable regional power supply.

Industrial and mining enterprises, along with large industrial parks, provide primary power supply for major factories, mines, metallurgical plants, chemical parks, and industrial bases. This infrastructure supports the startup and long-term stable operation of high-power equipment, serving as the backbone of industrial electricity demand.

Large-scale infrastructure and public buildings, including highway service areas, railway stations, water conservancy hubs, large shopping malls, and university towns, are powered by our high-voltage conversion solutions that ensure safe and reliable electricity supply.

Rural Power Grid Modernization and Remote Area Power Supply: In rural power grid upgrading and remote area power supply projects, these models have become the preferred choice due to their high cost-effectiveness and ease of maintenance, effectively improving rural power supply quality and coverage.