Dry distribution transformer

I. Product Introduction

The 35 kV class dry-line resin transformer is a core-type power transmission and distribution equipment designed for 35 kV voltage levels. Using advanced vacuum epoxy resin casting technology, it integrates high-voltage windings, iron cores, and low-voltage windings into a single unit, providing key advantages such as oil-free operation, safety, energy efficiency, and maintenance-free operation.

2. Basic technical parameters (subject to adjustment)

Nominal voltage: High voltage – 35 kV (with adjustment ±3×2.5%); Low voltage – standard for rated power 10 kV/0.4 kV

Rated power: 50 kVA–8000 kVA

Frequency: 50 Hz

Winding connection group: Dyn11 / Yyn0

Insulation class: F (tested according to class B temperature rise standards)

Permissible increase in winding temperature: no more than 80 K (class B)

Short circuit voltage: 4-6% (adjusted depending on power)

Partial discharge level: ≤10 pC

Noise level: ≤55 dB (at a distance of 1 meter from the unit)

Protection class: IP20–IP54 (selectable for indoor or outdoor installation)

Operating conditions: Air temperature from -25 °C to +55 °C; relative humidity ≤95% (non-condensing)

3. Key benefits

1. Fire-safe design with zero risk of fire

   A completely dry, oil-free transformer made of highly flammable epoxy resin is self-extinguishing, non-flammable, and does not emit toxic fumes. It eliminates the need for expensive oil-filled fire-fighting tanks, making it ideal for high-traffic environments such as shopping centers, hospitals, and subways.

2. Highest energy efficiency class I

   The use of high-quality textured silicon sheets for the core and highly conductive copper foil windings allows for no-load and load losses significantly lower than state standards, meeting Class I energy efficiency standards. Significant energy savings are achieved over long-term operation, while total operating and maintenance costs are minimal.

3. Increased resistance to short circuits

   The foil winding design, combined with integral vacuum casting, ensures high mechanical strength. The transformer withstands sudden overloads during short circuits, preventing winding deformation and burnout. The equipment's service life exceeds 30 years.

4. Low noise and environmentally friendly

   By optimizing the three-dimensional connection of the magnetic core and using modern vibration-damping technologies, the operating noise level is less than 55 dB, significantly lower than traditional oil-immersed transformers. Suitable for urban and indoor applications with stringent acoustic requirements.

5. Water-resistant, dust-proof and completely maintenance-free

   The one-piece sealed design ensures high resistance to moisture, corrosion, and dust, allowing for reliable operation in challenging conditions, including high humidity, dust, and coastal areas. No top-ups, filtration, or oil changes are required, ensuring a completely maintenance-free service life.

6. Low partial discharge and high reliability

   Vacuum casting technology eliminates internal voids and air inclusions in the windings, resulting in partial discharge levels below 10 pC—significantly lower than industry standards. This ensures stable insulation and reliable operation, surpassing that of oil-immersed transformers.

4. Application scenarios

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

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

2. High-end commercial and civil buildings • Application: super-tall 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 plants, electronic factories, data centers and precision machining shops.

• 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 fog content, cold areas and domestic power distribution in substations with photovoltaic/wind power enhancement.

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