On-site processing experience of dry-type transformer operating noise - News - Global IC Trade Starts Here Free Join

Transformer noise is a common issue that many users encounter, especially when the transformer is operating under certain conditions. While it's a natural characteristic of transformers, excessive noise can sometimes be a sign of underlying problems. National standards set strict limits on sound levels, but in practice, users often report higher noise levels than expected. This article explores some of the most common causes of transformer noise and offers practical solutions to reduce it.

1. Voltage Issues

High voltage can cause over-excitation in the transformer, leading to increased and sharper noises. To identify this, check the low-voltage output using a precise multimeter instead of relying solely on an indicator. Adjusting the high-voltage tap to a lower position can help reduce the over-excitation and minimize noise.

2. Resonance from Fans or Enclosures

Resonance from fans, enclosures, or other components can create unwanted noise, often mistaken for transformer noise. To check, press the casing or use a wooden stick to test different parts. If the noise changes, it’s likely due to resonance. Tightening screws or adding rubber pads can help fix the issue.

3. Installation Problems

Improper installation can increase vibration and amplify noise. Ensure the base is stable and the transformer is placed on a solid surface. Adding shock-absorbing pads can also help reduce noise levels.

4. Environmental Factors

The surrounding environment plays a significant role in how much noise a transformer produces. A large empty room with echoes or a transformer placed too close to walls can increase noise by up to 7dB. Installing sound-absorbing materials can significantly improve the situation.

5. Busbar Bridge Vibration

Vibrations in the busbar bridge caused by magnetic fields can greatly increase noise. Check if the noise changes with load or when pressing the busbar. Fixing loose connections or using soft connectors can help reduce the impact.

6. Core Resonance

Internal core resonance due to magnetic flux leakage can lead to abnormal sounds. Tightening all screws and adding shock-absorbing pads can help stabilize the core and reduce noise.

7. Coil Vibration

When heavy currents pass through the windings, vibrations can occur. Increasing axial pressure on the coils or adjusting the positioning can help reduce these vibrations and the resulting noise.

8. Load Characteristics

Non-linear loads, such as rectifiers or frequency converters, can distort the voltage waveform and introduce additional noise. Using harmonic filters can help mitigate this issue.

9. Phase Loss

A missing phase in the power supply can cause uneven excitation and noise. Checking the power supply and fuses can help identify and resolve the problem.

10. Poor Contact

Loose contacts or misaligned switches can result in intermittent noise. Inspecting and tightening all connections is essential for proper operation.

11. Floating Potential Discharge

Components like channel steel or bolts may develop floating potentials due to poor contact. This can produce faint discharge sounds, which are often mistaken for internal faults. Painting or cleaning affected areas can help eliminate this issue.

12. Ground Faults or Short Circuits

A ground fault or short circuit on the low-voltage side can cause loud noises. The closer the fault is to the transformer, the louder the sound becomes. Immediate action is required to prevent damage.

13. Transformer Variability

Different manufacturers, types, and environments can result in varying noise levels. It's important to understand that some level of noise is normal and does not necessarily indicate a problem.

14. Misunderstanding of Dry-Type Transformers

Users who have previously used oil-filled transformers may expect similar noise levels from dry-type ones. However, dry-type transformers are designed differently, and their noise is more noticeable due to the lack of insulation. This is a normal characteristic and doesn’t affect performance.