5 Uses Of Transformer

In modern society, transformers are indispensable core components of power systems, ensuring that electricity is transmitted efficiently and safely from power stations to households and various enterprises. Whether it’s traditional oil-immersed transformers or modern dry-type transformers, power transformers are crucial in different application scenarios. This article will explain the application directions of transformers from five perspectives.

Household and Commercial Power Supply

The most fundamental use of transformers is to provide stable electricity to households and commercial buildings. In the final stage of power distribution, transformers step down high-voltage electricity to low-voltage levels suitable for daily use (such as 220V or 110V). Oil-immersed transformers, due to their efficient heat dissipation, are commonly used in outdoor distribution, while dry-type transformers, with their high safety, are widely applied in commercial buildings.

Case Study: Shanghai Pudong New Area Residential Distribution Upgrade 
In a renovation project for an old residential area in Shanghai’s Pudong New Area, the local power company employed multiple 10kV oil-immersed distribution transformers to step down the high-voltage grid electricity to the low voltage required by residents. Installed in outdoor distribution boxes, these transformers, with their excellent cooling performance, ensured stable power supply during peak summer demand, relieving residents of concerns about frequent outages.

Power Support in Industrial Production

The industrial sector has a high and stringent demand for electricity, and transformers adjust voltage to provide reliable power support for heavy machinery. Oil-immersed transformers, with their high capacity and durability, are often used in large-scale industrial settings, while dry-type transformers are better suited for factories with higher safety and environmental requirements.

Case Study: Volkswagen Factory in Germany
Volkswagen’s factory in Wolfsburg, Germany, uses multiple 35kV dry-type transformers to power welding robots and stamping equipment on the production line. Installed inside the factory, these transformers leverage air cooling and an oil-free design to avoid oil leakage risks while meeting strict EU environmental standards, ensuring safe and efficient production.

Long-Distance Power Transmission

Transformers are vital in long-distance power transmission. Step-up transformers increase the low-voltage electricity from power stations to high voltage (such as 110kV or higher) to reduce transmission losses, while step-down transformers lower the voltage at the consumption end. Oil-immersed transformers, due to their excellent insulation and high load capacity, are typically used in such high-voltage applications.

Case Study: China’s West-to-East Electricity Transmission Project
In China’s “West-to-East Electricity Transmission” project, large oil-immersed power transformers are widely deployed. For instance, a hydropower station in Guizhou uses 500kV oil-immersed step-up transformers to transmit hydropower to eastern coastal cities. These transformers operate stably even in extreme weather, ensuring efficient power transmission over thousands of kilometers.

Integration of Renewable Energy Systems

Renewable energy sources like wind and solar have fluctuating outputs, and transformers adjust voltage and stabilize current to integrate them into the grid. Dry-type transformers, due to their simple maintenance and eco-friendly features, are often used in small-scale renewable energy projects, while oil-immersed transformers are more suitable for large-scale power plants.

Case Study: Denmark’s Vestas Wind Farm
Denmark’s Vestas company employs multiple 66kV oil-immersed transformers in its North Sea wind farm. These transformers step up the electricity generated by wind turbines for grid connection, relying on the efficient heat dissipation of their oil-cooling systems to ensure stable power output despite varying wind speeds. This project supplies clean energy locally and reduces carbon emissions.

Power System Protection and Fault Management

Transformers not only convert electricity but also play a role in power system protection. They work with devices like circuit breakers to monitor anomalies and isolate faults. Oil-immersed transformers prevent overheating through oil temperature monitoring, while dry-type transformers, with their high-temperature-resistant insulation materials, reduce fire risks.

Case Study: Tokyo Electric Power Company’s Emergency System
Tokyo Electric Power Company uses multiple 20kV dry-type transformers equipped with smart monitoring systems in its urban distribution network. During a lightning-induced short-circuit event, these transformers quickly isolated the fault area, preventing a wider blackout. Their oil-free design also reduced the risk of fire spread, ensuring power safety in densely populated areas.

The Value and Selection of Transformers

The five uses above—household power supply, industrial support, long-distance transmission, renewable energy integration, and system protection—demonstrate the versatility of transformers in power systems. Oil-immersed transformers excel in efficiency and durability, making them suitable for outdoor and high-load scenarios; dry-type transformers, with their safety and environmental advantages, are gradually gaining ground in indoor and specialized markets. Real-world cases show that selecting the right transformer type requires comprehensive consideration of the application environment and needs.

Future Outlook

With the development of smart and green technologies, transformers are continuously upgrading. Smart transformers optimize performance in real-time via sensors, while new materials improve energy efficiency and lifespan. For example, future oil-immersed transformers may use more eco-friendly ester oils, and dry-type transformers might increase capacity to adapt to more scenarios.