Manufacturing of Amorphous Alloy Transformers: Technical Key Points and Process Analysis

　　1. Core Materials and Processes

　　1.1 Amorphous Alloy Strip

　　Material Properties:

　　Amorphous alloys (e.g., Fe-Si-B series) are produced via rapid solidification technology, featuring a disordered atomic arrangement with no grain boundaries or dislocations, resulting in high magnetic permeability and low coercivity.

　　Key Parameters:

　　Thickness: 22–25 μm (ultra-thin structure reduces eddy current losses).

　　Saturation Magnetic Flux Density: 1.56–1.58 T (slightly lower than silicon steel but sufficient for distribution transformers).

　　Losses: No-load losses are 60%–70% lower than those of silicon steel.

　　1.2 Core Manufacturing Process

　　Winding Forming:

　　Amorphous strips are wound into cores using specialized winding machines, requiring precise tension control (to avoid brittle fracture) and a stacking factor typically ranging from 0.82 to 0.85.

　　Analogy: The winding process resembles "rolling toilet paper" but demands far more precise tension control.

　　Annealing Treatment:

　　Cores undergo annealing at 350–400°C in a vacuum or inert gas environment to eliminate stress and restore magnetic properties.

　　Key Point: Excessive annealing temperatures cause crystallization (degrading performance), while insufficient temperatures leave residual stress.

　　2. Winding and Structural Design

　　2.1 Winding Design

　　Material Selection: High-conductivity copper or aluminum conductors are used, with optimized cross-sectional shapes (e.g., rectangular, transposed conductors) to reduce resistive losses.

　　Insulation Treatment:

　　Nomex paper, epoxy resin, or other high-temperature-resistant insulation materials are applied between windings to ensure partial discharge ≤ 5 pC.

　　Example: The SCBH15 series transformer maintains a winding temperature rise ≤ 65 K (exceeding national standard requirements).

　　2.2 Structural Optimization

　　Core-Winding Coupling: A "rigid body clamping + elastic support" structure is adopted to reduce vibration and noise (noise level ≤ 45 dB).

　　Thermal Design:

　　Natural cooling (AN) or forced-air cooling (AF) methods are employed. For oil-immersed transformers, oil channel structures (e.g., corrugated tanks) are optimized.

　　3. Manufacturing Process Control

　　3.1 Key Process Steps

　　3.2 Quality Control

　　No-Load Loss Testing: High-precision power analyzers (accuracy ≤ 0.1%) are used to ensure measured values ≤ 1.05 × nominal value.

　　Temperature Rise Testing: Simulated full-load operation monitors top-oil temperature rise and winding hotspot temperature rise.

　　4. Performance Advantages and Challenges

　　4.1 Advantages

　　High Efficiency: No-load losses are 40%–50% lower than those of S13-type transformers, reducing lifecycle costs by 20%–30%.

　　Environmental Friendliness: Production energy consumption is 70% lower than that of silicon steel cores, and materials are recyclable.

　　4.2 Challenges

　　Brittleness Issue: Amorphous strips have only 1/3 the bending strength of silicon steel, necessitating optimized winding and annealing processes.

　　Cost Pressure: Amorphous strip prices are 30%–50% higher than those of silicon steel, requiring cost reduction through scaled production.

　　5. Typical Application Cases

　　5.1 Urban Power Distribution

　　In a city grid upgrade project, SCBH15-1000 kVA amorphous alloy transformers replaced S11 models, achieving annual energy savings of 68,000 kWh and reducing CO₂ emissions by 54 tons.

　　5.2 Industrial Sector

　　A steel plant replaced 10 S11-1600 kVA transformers with amorphous alloy models, saving over ¥5 million annually in electricity costs, with a payback period of 3.2 years.

　　6. Future Development Trends

　　Material Innovation: Development of high-Bs (≥1.6 T) amorphous alloys to enhance transformer capacity and efficiency.

　　Intelligent Manufacturing: Introduction of AI vision inspection and automated winding equipment to improve production consistency and yield.

　　System Integration: Integration with smart grids to enable transformer condition monitoring and energy efficiency optimization.

　　7. Procurement and Usage Recommendations

　　Priority Selection: Choose products compliant with GB 20052-2020 Tier 1 Energy Efficiency standards, focusing on no-load and load loss indicators.

　　Operation and Maintenance Tips:

　　Avoid prolonged overloading (recommended load rate ≤ 80%).

　　Regularly inspect insulation resistance (≥ 500 MΩ) and partial discharge.

　　Summary

　　Amorphous alloy transformers offer significant advantages in energy efficiency through material innovation and process optimization, particularly suited for light-load or intermittent-load scenarios. Despite challenges related to brittleness and cost, their market prospects are promising with technological advancements and scaled applications. For users, selecting compliant products and strengthening maintenance management can maximize energy-saving benefits.