dry-type transformers

I. Product Introduction

Dry-type linear resin-encapsulated transformer of 35 kV class is a core power transmission and distribution equipment designed for voltage levels of 35 kV. Utilizing advanced vacuum casting technology with epoxy resin, it integrates high-voltage windings, iron cores, and low-voltage windings into a single unit, offering key advantages such as oil-free operation, safety, energy efficiency, and maintenance-free performance.

2. Main technical parameter specifications (customizable)

Rated Voltage | High Voltage: 35 kV (±3×2.5%); Low Voltage: rated capacity 10 kV/0.4 kV | Frequency 50KVA-8000KVA | Connection Group 50 Hz | Insulation Class Dyn11/Yyn0 | Class F Windings (tested according to Class B temperature rise criteria) Temperature Rise Limit | Windings ≤80K (Class B) Short Circuit | 4%–6% (adjustable based on capacity) Partial Discharge Level | ≤10 pC Noise Level | ≤55 dB (1 m distance from equipment) Protection Rating | IP20–IP54 (indoor/outdoor selectable) Operating Environment | Temperature: -25°C to +55°C; Humidity: ≤95% (non-condensing)

3. Key features

1. Inherently safe design with zero fire risk. Fully dry construction without oil using high fire-resistant epoxy resin casting, ensuring non-flammable, non-explosive properties and no emission of toxic fumes. This eliminates the need for expensive fire oil tanks, making it a priority for safety in crowded spaces such as shopping malls, hospitals, and subways.

2. Class I energy efficiency with extreme savings: Using high-quality oriented silicon steel sheet cores and high-conductivity copper foil windings, no-load and load losses are significantly lower than national standards, meeting the national Class I energy efficiency standard. Long-term operation demonstrates an impressive energy-saving effect, with comprehensive operation and maintenance costs being among the lowest in the world.

3. Exceptionally high short-circuit resistance: Thanks to the foil-wound coil design combined with integrated epoxy casting, it possesses ultra-high mechanical strength, effectively withstanding sudden short-circuit overvoltages in the power grid and preventing coil deformation and burnout. The equipment service life exceeds 30 years.

4. Low-noise operation and environmental friendliness: By optimizing the 3D iron core joint and utilizing advanced vibration damping technologies, the operating noise is controlled below 55 dB, significantly lower than that of traditional oil-immersed transformers, making it suitable for urban and indoor installations with strict acoustic requirements.

5. Moisture and dust resistance: Integrated maintenance-free sealing and full lifecycle design provide excellent moisture and corrosion resistance, ensuring stable operation in harsh environments such as high humidity, dust, and coastal areas. No oil refilling, filtration, or replacement is required, achieving true maintenance-free operation.

6. Extremely low partial discharge with reliable operation. The vacuum casting process ensures no internal bubbles or air gaps in the coil, resulting in partial discharge (≤10 pC) significantly below industry standards. It demonstrates superior thermal insulation and power supply reliability, greatly outperforming oil-immersed transformers.

4. Application scenarios

1. Urban core infrastructure • Scenarios: subway stations, high-speed railway stations, airports, tunnels, and large-scale underground complexes.

• Requirements: low noise, safety, fire resistance, and explosion resistance to ensure stable power supply for major transportation hubs.

2. Premium commercial and civil buildings • Application: super high-rise office buildings, five-star hotels, large shopping malls, and high-end residential complexes.

• Requirements: high efficiency and energy saving. Compact space and silent operation, meeting green building standards.

3. Large industrial complexes • Applications: petrochemical plants, metallurgical enterprises, electronics factories, data centers, and precision machining workshops.

• Requirements: High short-circuit resistance, moisture and pollution resistance, high reliability to ensure continuous production without power outages.

4. Special environments and new energy • Applications: coastal areas with high salt spray, cold regions, and internal power distribution in substations with photovoltaic/wind power boosting.

• Requirements: corrosion resistance, cold resistance, high thermal insulation, and adaptation to various complex climates and energy topologies.