Dry distribution transformer

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 parameters (subject to adjustment)

Rated voltage: High voltage – 35 kV (with ±3×2.5% regulation); 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 (tests conducted according to class B temperature rise standards)

Allowable winding temperature rise: not exceeding 80 K (class B)

Short-circuit voltage: 4–6% (adjustable based on power)

Partial discharge level: ≤10 pC

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

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

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

3. Key advantages

1. Fire-safe design with zero fire risk

   Fully dry-type oil-free transformer based on highly flame-retardant epoxy resin, non-combustible, non-explosive, and emitting no toxic fumes. Eliminates the need for costly fireproof oil tanks, making it ideal for crowded facilities such as shopping malls, hospitals, and subways.

2. Highest Class I energy efficiency

   The use of high-quality textured silicon steel sheets for the core and highly conductive copper foil windings achieves no-load and load losses significantly below national standards, meeting Class I energy efficiency. During long-term operation, substantial electricity savings are ensured, and the total operational and maintenance costs are minimized.

3. Enhanced short-circuit resistance

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

4. Low noise and environmental friendliness

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

5. Moisture resistance, dust protection, and completely maintenance-free

   The integrated sealed structure provides high resistance to moisture, corrosion, and dust, enabling stable operation in harsh environments such as high humidity, dusty conditions, and coastal areas. No oil refilling, filtering, or replacement is required, ensuring complete maintenance-free operation throughout the entire service life.

6. Low partial discharge level and high reliability

   Vacuum casting technology eliminates internal voids and air inclusions in the windings, so the partial discharge level does not exceed 10 pC – significantly lower than industry standards. It ensures stable insulation and reliable operation, surpassing the performance of 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.