Amorphous alloy transformers, developed in the 1970s, represent a new generation of power transformers that utilize amorphous alloys as the core material instead of conventional silicon steel sheets. Compared to silicon steel-core transformers, they reduce no-load losses by approximately 70%–80% and no-load current by about 85%. These transformers are currently among the most energy-efficient distribution transformers available, making them ideal for applications in areas with low load utilization and high fire safety requirements—such as rural power grids, high-rise buildings, commercial centers, subways, airports, railway stations, industrial and mining enterprises, and power plants.
Amorphous Alloy Ribbons
Amorphous alloy ribbons are produced by combining elements such as iron, cobalt, carbon, silicon, and boron in precise proportions. The mixture is melted at high temperatures and then rapidly solidified using a high-speed rotating wheel, with a cooling rate reaching up to 1,000,000°C per second. This extreme cooling prevents the formation of crystalline lattice structures, resulting in a disordered, amorphous atomic arrangement.
Formation of Amorphous Alloys
Typically, when metals or alloys solidify from a liquid state, atoms transition from a disordered liquid phase to an ordered solid crystalline structure. However, with an extremely high cooling rate, atoms do not have sufficient time to arrange into a regular lattice and are instead "frozen" in a disordered state—similar to the structure of liquids—forming what is known as an amorphous alloy.
For pure metals to achieve an amorphous structure, an exceptionally high cooling rate is required. Due to current technological limitations, achieving such rates in large-scale production is impractical, making it difficult to produce amorphous structures from pure metals.
To overcome this, amorphous metals are typically produced by alloying base metals with other elements. Alloys composed of atoms with different sizes and properties have lower melting points and are more prone to forming amorphous structures during rapid solidification.
The amorphous alloy used in transformer cores is an iron-based alloy, rapidly solidified into thin ribbons at a cooling rate of one million degrees per second, with a thickness of only 0.03 mm.
Advantages of Amorphous Alloy Transformers
Energy Efficiency
The use of amorphous alloy cores, combined with an advanced three-phase three-column manufacturing process, significantly reduces core losses. No-load losses are reduced to approximately 25% of those in conventional dry-type transformers. Although the initial cost of amorphous alloy cores is higher, the exceptional efficiency and energy-saving performance allow the additional investment to be recovered within 3–5 years under an average load of 60%. Over the transformer’s 30-year service life, substantial savings in electricity costs can be achieved.
Reliability
H-Class Insulation (180°C operating temperature): Offers excellent thermal resistance.
Durability: Capable of withstanding harsh storage and transportation conditions.
Robust Performance: Operates reliably under adverse environmental conditions (including extreme climates and geographical settings); can sustain 120% overload for extended periods.
Short-Circuit Resistance: Demonstrates superior resistance to short-circuit forces.
Maintenance-Free: Requires virtually no maintenance under normal operating conditions.
Safety
Non-Flammable: Will not ignite, resists fire, and does not explode or emit toxic gases during operation.
Environmental Resilience: Less sensitive to temperature fluctuations, dust, and pollution.
Crack Resistance: Does not develop cracks over time.
Environmental and Human Safety: Safe for human health and the environment, with no harmful effects on surrounding equipment.
Environmental Benefits
Eco-Friendly: Causes no environmental pollution during manufacturing, transportation, storage, or operation.
Recyclable: Coils and core materials can be recycled at end-of-life, enabling resource reuse without environmental harm.
Low Noise: Advanced core design and manufacturing techniques ensure noise levels are 4–5 dB below current national standards.
For example, a 2000 kVA SCRBH15-2000 amorphous dry-type transformer operating at 60% load can save approximately 24,000 kWh of electricity annually. At an electricity cost of 1 RMB per kWh, this translates to annual savings of 24,000 RMB. Currently, the market price for a comparable SCB10-2000 transformer is around 450,000 RMB, while the amorphous version costs about 550,000 RMB—approximately 20% higher. However, the reduction in operational costs over a five-year period can fully offset the higher initial investment.