Amorphous Alloy Dry-Type Transformer

Amorphous Alloy Dry-Type Transformer

An amorphous alloy dry-type transformer is a high-efficiency, energy-saving power distribution device that utilizes an amorphous metal ribbon core and air as the cooling medium, eliminating the need for insulating oil.

Principle:
The metallic atoms in amorphous alloy materials possess a disordered, non-crystalline atomic structure, resulting in extremely low hysteresis loss compared to conventional silicon steel. When subjected to alternating voltage, the core undergoes rapid cyclic magnetization with drastically reduced excitation energy consumption. Windings rely on natural air convection or forced-air cooling (AN/AF) for heat dissipation. Furthermore, the core adopts a wound configuration, ensuring that the magnetic flux flows smoothly along the material's easy magnetization direction, which further minimizes no-load losses.

Core Advantages:

• Exceptional Energy Efficiency: No-load losses are approximately 70% to 75% lower than those of standard silicon steel dry-type transformers, offering massive energy-saving benefits during long periods of light-load operation.

• Superior Fire Safety: Non-combustible, risk-free from oil leaks, and possessing excellent explosion-proof properties.

• Reliable Operation & Low Maintenance: Features low operating noise, strong overload capacity, and an eco-friendly design that requires zero oil sampling, testing, or replacement, significantly simplifying routine maintenance.

• Limitations: The core exhibits relatively lower mechanical impact resistance, and initial equipment procurement costs are higher than traditional dry-type models.

Application Scenarios:
Primarily deployed in high-safety and strict fire-prevention environments, such as high-rise buildings, commercial complexes, hospitals, subways, data centers, schools, and underground utility tunnels. It is also widely utilized in indoor substations, industrial plant distribution, and renewable energy integration (such as solar and wind power step-up systems), perfectly aligning with modern grid decarbonization and energy-saving initiatives.

Quality Assurance & Core Process：

1. Amorphous Alloy Ribbon

We adopt high‑quality amorphous alloy ribbon as transformer core material, featuring ultra‑low core loss performance far superior to conventional grain‑oriented silicon steel. The nominal thickness of amorphous ribbon is only 0.025 mm. The closed wound core is produced by specialized slitting and winding equipment to minimize mechanical stress on the amorphous material. The core is assembled with optimized clamping force to avoid brittle fracture of amorphous strips. This design delivers outstanding no‑load loss reduction, excellent energy‑saving performance and stable magnetic properties under operating conditions.

2. High-Conductivity Winding Conductors & Core-Coil Assembly

High-conductivity electrolytic copper or aluminum conductors are selected based on transformer capacity, voltage class, and loss requirements. Incoming materials undergo stringent quality inspections for dimensions, electrical resistance, surface quality, and traceability. During the winding process, conductor tension, winding height, layer insulation, and conductor positioning are precisely controlled to ensure resistance consistency and mechanical stability, thereby minimizing load losses and temperature rise during operation.

During core-coil active part assembly, coil height, axial clamping force, radial support, and spacer block positioning are precisely controlled. Proper mechanical clamping prevents coil displacement during transport, normal operation, and short-circuit conditions. Meanwhile, clamping forces are strictly regulated to avoid excessive stress on conductors and insulation materials. Our mechanical design accounts for both radial and axial electromagnetic forces, safeguarding short-circuit withstand capability and long-term dimensional stability.

3. Advanced Insulation System (Oil-Immersed & Dry-Type)

For oil-immersed transformers, we utilize high-grade insulation materials, including Kraft paper, thermally upgraded paper, pressboard, and transformer-grade laminated board. For dry-type transformers, we employ DMD, NMN, Nomex, fiberglass, and epoxy resin systems. Insulation thickness, overlap width, oil duct dimensions, electrical clearances, and mechanical positioning are strictly regulated. All insulation materials are stored under climate-controlled conditions to minimize moisture absorption and contamination, ensuring stable dielectric strength and long-term insulation reliability.

4. Controlled Vacuum Drying

We apply a controlled drying curve regulated by temperature, vacuum level, and duration parameters, rather than relying on fixed cycle times. The process comprises controlled pre-heating, evacuation, primary drying, and final soak phases, with continuous temperature and vacuum monitoring and logging. End-point determination is based on validated process criteria and moisture limits. This process minimizes residual moisture in cellulose insulation, maximizing dielectric strength, retarding insulation aging, and extending overall service life.

5. Vacuum Epoxy Resin Casting

For cast-resin dry-type transformers, we utilize controlled vacuum casting technology. Resin-to-hardener ratio, material temperature, vacuum level, mixing time, pouring conditions, and curing temperatures are strictly regulated. Vacuum degassing minimizes micro-voids prior to pouring, while controlled curing ensures stable mechanical and thermal properties. Finished coils undergo thorough visual and electrical inspections, including routine partial discharge (PD) testing. This process eliminates internal voids, ensuring reliable insulation performance throughout the transformer's service life.

6. Clean Assembly & Torque Control

Final assembly takes place in a controlled environment to minimize contamination from dust, metallic particles, and foreign objects. Critical components are inspected for cleanliness, dimensional accuracy, and insulation condition. Electrical clearances, lead routing, grounding connections, and mechanical supports are rigorously controlled throughout assembly. Critical bolted joints are tightened to specified torque values using calibrated equipment and fully logged. Prior to sealing the tank or enclosure, a thorough internal inspection ensures no tools, loose parts, or foreign material remain.

7. 100% Factory Routine Testing

Every transformer undergoes 100% routine testing prior to dispatch, complying with applicable IEC standards, approved technical specifications, and customer requirements. Standard test routines include winding DC resistance, voltage ratio, vector group verification, no-load loss and current, load loss and short-circuit impedance, applied voltage withstand, and induced overvoltage withstand tests. Special tests—such as partial discharge (PD), dissipation factor (tan δ), or sweep frequency response analysis (SFRA)—are conducted upon request. Each unit is assigned a unique serial number linked to its material records, manufacturing data, and final test reports, ensuring end-to-end traceability.

Youth Transformer Co.,Ltd.