Product Details of 35kV SCB18 Epoxy Resin Cast Dry-Type Transformer

I. Product Overview

The 35kV SCB18 epoxy resin cast dry-type transformer is the highest energy efficiency grade product among 35kV dry-type transformers at present, representing the top level of domestic dry-type transformer technology. It is specially designed for scenarios with extreme requirements on ultra-low loss, ultra-low noise, high reliability and long service life, such as power grid upgrading, data centers, high-end public buildings, new energy and industrial energy-saving renovation.

Model designation:

• S: Three-phase

• C: Epoxy resin cast insulation

• B: Low-voltage foil winding

• 18: High-performance, ultra-low loss code

• 35kV: Rated high voltage level

It adopts an oil-free structure, vacuum epoxy casting, multi-step stepped core and integrated intelligent temperature control design. It has the advantages of Level 1 energy efficiency, flame retardancy, explosion-proof, moisture-proof, dust-proof, short-circuit withstand, maintenance-free and ultra-long service life, fully meeting the development needs of modern power grids for green, low-carbon, safe, intelligent and unattended operation.

Applicable standards:

GB/T 10228, GB 1094.11, GB 20052-2024 (Level 1 energy efficiency), IEC 60076 series.

Flame retardant class: FV-0, eco-friendly, oil-free, no toxic gas emission.

II. Key Technical Parameters(Customizable)

• Rated voltage: 35kV (off-circuit tap ±2×2.5%) / 0.4kV

• Rated capacity: 30kVA～3150kVA (commonly 630～2500kVA)

• Connection group: Dyn11 (standard)

• Frequency: 50Hz

• Insulation class: Class F (155℃)

• Cooling mode: AN (natural air cooling) / AF (forced air cooling)

• Protection degree: IP20 / IP30 / IP40 / IP54 (outdoor type)

• Short-circuit impedance: 6% (standard)

• Partial discharge: ≤5pC (far better than national standard)

• Noise level: 40～45dB(A) (top level in the industry)

• Ambient temperature: -25℃～+45℃

• Altitude: ≤1000m (plateau type customizable)

• Design service life: ≥30 years

Loss comparison (core advantages):

• No-load loss reduced by 8%～12% compared with SCB14

• Load loss reduced by 6%～10% compared with SCB14

• Lower no-load current, lower grid loss, higher power factor

• For 1000kVA transformer (8000h/year, 70% load rate), power saving exceeds 1000 kWh per year

III. Structural and Technological Highlights

1. Core: Ultra-low loss & extreme silence

• Adopts 0.23mm～0.27mm ultra-high permeability grain-oriented silicon steel sheet with high magnetic conductivity and extremely low loss.

• Nine-step step-lap joint and stepped lamination ensure uniform magnetic circuit, minimum magnetic resistance and minimum vibration.

• Integral epoxy sealed coating for moisture-proof, rust-proof, corrosion-proof and noise radiation reduction.

• High-strength non-magnetic binding strap plus elastic damping structure, no loosening or abnormal noise during operation.

• Noise level is 3～5dB(A) lower than SCB14, close to ambient background noise.

2. Winding: High strength, high insulation & strong short-circuit withstand

• Low-voltage foil winding: integrally wound with high-precision oxygen-free copper foil, uniform current distribution and extremely low eddy current loss.

• High-voltage multi-layer cylindrical winding: balanced ampere-turns, uniform interlayer insulation, excellent ability to withstand sudden short circuit.

• Vacuum epoxy casting with fiberglass reinforcement: no bubbles, no voids, no weak points, high integrity.

• Insulation features high impact resistance, moisture resistance, pollution resistance, no cracking and no aging.

• Flame retardant class FV-0, smokeless, non-toxic, non-flammable during combustion, meeting the highest fire protection requirements.

3. Temperature control & intelligent monitoring system

• PT100 platinum resistors embedded inside windings for accurate, stable and reliable temperature measurement.

• Intelligent temperature controller: over-temperature alarm, trip, automatic fan control, fault memory and historical query.

• Standard RS485/Modbus communication, compatible with SCADA, power monitoring and IoT platforms.

• Supports remote temperature monitoring, fault pre-alarm, energy consumption statistics and unattended operation.

• Optional: optical fiber temperature measurement, dehumidification & heating, harmonic monitoring, fire protection linkage interface.

4. Assembly and enclosure

• Integrally cured structure with high mechanical strength, seismic resistance, short-circuit resistance and transportation impact resistance.

• Fully sealed structure, moisture-proof, dust-proof, salt-fog resistant, anti-condensation and chemical corrosion resistant.

• High-quality steel enclosure with electrostatic spraying, aesthetic, anti-corrosion and durable.

• Optimized ventilation louvers for higher heat dissipation efficiency and lower temperature rise.

• Equipped with rain cover, dustproof net and base for direct outdoor installation.

IV. Core Performance Advantages

1. Level 1 energy efficiency, extreme energy saving

• National highest Level 1 energy efficiency, losses far lower than national standard limits.

• More power-saving than SCB13 and SCB14, with the lowest long-term operating cost.

• Suitable for 24-hour uninterrupted high-load scenarios such as data centers, power grids, industry and commerce.

• Reduces grid line loss, improves power factor and cuts reactive power compensation investment.

2. Highest safety level

• Full oil-free design, no leakage, fire or explosion risks.

• Can be directly installed indoors, in basements, high-rise buildings and load centers.

• No oil pits, firewalls or fire pipelines required, greatly reducing civil engineering investment.

• Meets the highest fire standards for crowded places such as hospitals, schools, subways, airports and shopping malls.

3. Top-tier short-circuit withstand capability in the industry

• Foil + cylindrical winding structure, short-circuit impact resistance far exceeds national standards.

• High insulation integrity, no cracking, no aging, extremely low long-term operation failure rate.

4. Ultra-low noise, environment-friendly

• Triple noise reduction (core + winding + assembly), noise ≤45dB(A).

• Fully suitable for noise-sensitive areas such as residential quarters, hospitals, schools, office buildings and laboratories.

5. Super strong environmental adaptability

• Moisture-proof, dust-proof, salt-fog resistant, pollution resistant and anti-condensation.

• Operates stably for a long time in coastal, chemical, mining, humid, dusty and plateau environments.

• No pre-drying needed before restart after shutdown, with very little maintenance.

6. Maintenance-free & ultra-long service life

• Oil-free structure, no oil change, oil filtration or oil test required.

• Routine maintenance only includes regular dust cleaning and inspection of terminals and temperature controller.

• Normal service life ≥30 years, far longer than ordinary dry-type transformers.

7. High degree of intelligence

• Supports remote monitoring, fault pre-alarm and energy consumption analysis.

• Perfectly suitable for smart substations, unattended stations and digital new infrastructure.

V. Full Range of Applications

• Power grid systems: 35kV substations, urban distribution networks, industrial park step-down stations, power grid energy-saving upgrading.

• Data centers & new infrastructure: IDC, cloud computing centers, big data industrial parks, computing centers (preferred for low PUE).

• High-end public buildings: airports, subways, high-speed rail stations, hospitals, schools, shopping malls, office buildings, high-rise buildings.

• New energy power generation: 35kV collector stations of PV and wind farms, energy storage power station supporting facilities.

• Hazardous industrial environments: petroleum, chemical, coal, pharmaceutical, metallurgical and flammable & explosive places.

• Special environments: coastal high salt fog, humid & rainy, heavy pollution, plateau, low temperature and noise-restricted areas.

VI. Installation, Operation and Maintenance

• Install on a level and firm foundation with good ventilation and smooth air inlet and outlet.

• Reliable grounding of the enclosure, grounding resistance ≤4Ω.

• Conduct tests before commissioning: insulation, transformation ratio, DC resistance, power frequency withstand voltage and partial discharge.

• Regularly clean dust on fans, filters and enclosure to ensure good heat dissipation.

• Periodically check wiring terminals, fasteners, temperature controller and fan functions.

• Oil-free maintenance, truly realizing “one-time installation, long-term ease of use”.