9 May 2023
Dry-type transformers, a type of air-cooled transformer, have become increasingly popular in recent years. Dry-type transformers are characterized by the absence of liquid insulation in their windings and magnetic core. Their versatility has led to a wide range of applications.
Applications of Dry-Type Transformers:
Because they do not pose a risk of explosion, dry-type transformers have a broad range of applications. Some of these applications include:
- Shopping malls
- Office buildings
- Pump stations
- Railway systems and dams
Features of Dry-Type Transformers:
- They are reliable in preventing fires. They have the capability for rapid fire suppression in case of a fire.
- They can operate without maintenance even in highly humid environments and are resistant to moisture.
- They maintain safety even in areas with a high concentration of people, provided they are properly maintained.
- Due to their winding structures, they are resistant to short circuits.
- The epoxy used in insulation is non-flammable and self-extinguishing.
- Low-voltage and high-voltage cables are manufactured in a closed environment. They can also be made with cast resin and under vacuum.
Differences Between Oil-Immersed and Dry-Type Transformers:
While oil-immersed and dry-type transformers are different types of transformers, they are often compared. Here are the differences between the two:
- Dry-type transformers are generally more expensive than oil-immersed transformers due to their lack of explosion risk.
- Dry-type transformers require less maintenance compared to oil-immersed transformers.
- Dry-type transformers do not have a risk of causing fires because they lack oil, which is present in oil-immersed transformers.
- Dry-type transformers can be safely used in areas with a high concentration of people because they do not pose an explosion risk.
- Dry-type transformers may require additional equipment such as cooling fans. Tap changers and connection groups can be adjusted as needed.
Maintenance of Dry-Type Transformers:
While dry-type transformers require less maintenance compared to other transformer types, periodic maintenance is still essential. Here’s how to prepare for the maintenance of a dry-type transformer:
- Ensure that the transformer is completely de-energized.
- To de-energize the transformer, open the circuit breaker at the transformer’s input and disconnect the power supply.
- After opening the circuit breaker, also open the disconnect switch.
- All necessary precautions should be taken before performing transformer maintenance.
- Refer to the user manual and maintenance instructions for the relevant year published by the electricity distribution company (TEDAŞ) before conducting maintenance.
- High Voltage Transformer Repair, Maintenance, and Restoration
- The Importance of Transformer Repair, Maintenance, and Service
- Transformer (Trafo)
- Power Transformer
- Tip Test and Temperature Rise Test
- Tip Test and Measuring Audible Noise Level
- Special Tests
- Induced Voltage Test for Transformers
- Short-Circuit Test