As a core component of the power system, power transformers transfer electrical energy between different circuits through electromagnetic induction, performing the critical function of voltage conversion in transmission and distribution systems — stepping up voltage for long-distance transmission and stepping down voltage for end-user distribution. However, noise generated during operation is a widespread issue that cannot be overlooked. This article systematically analyzes the causes of transformer noise and proposes targeted control strategies.

Analysis of Main Causes of Transformer Noise:

1.Core Magnetostrictive Vibration: When the transformer is energized, the alternating magnetic field causes magnetostriction in the silicon steel sheets, leading to periodic deformation of the core. This results in fundamental vibrations and noise at twice the power frequency (100 Hz/120 Hz).

2.Mechanical Structural Resonance: Mechanical factors such as winding vibration due to electromagnetic forces, loose connections, and cooling equipment operation can induce structural resonance, particularly noticeable during load fluctuations.

3.High-Frequency Noise Caused by Discharge Phenomena: Insulation anomalies such as internal partial discharge and corona discharge generate high-frequency vibrations and harsh noise across a broad frequency band.

4.Harmonic Amplification Effect: Harmonics in the power system distort the excitation current, intensifying core vibration and potentially exciting resonance at specific frequencies, significantly elevating noise levels.

Comprehensive Solutions for Transformer Noise Control:

Transformer noise not only affects the surrounding environment but may also accelerate equipment aging due to long-term vibration. Effective noise control requires a multi-level integrated approach:

1.Source Control — Optimizing Design:

• Use stepped-lap core joints and high-permeability silicon steel sheets to reduce magnetostriction.
• Optimize winding clamping structures and core fastening techniques to enhance mechanical stiffness.
• Select low-noise cooling equipment and install vibration-damping foundations.

2.Pathway Control — Acoustic Management Techniques:

• Apply sound-absorbing materials (e.g., porous fiber composites) inside the transformer tank.
• Install noise enclosures or build sound barriers, with emphasis on low-frequency noise isolation design.
• Incorporate elastic damping elements in vibration transmission paths.

3.System-Level Management — Improving Operational Environment:

• Install active filtering devices to suppress system harmonics.
• Establish an online vibration and noise monitoring system to enable anomaly detection and early warning.
• Regularly inspect fastener torque and assess structural conditions.

Conclusion:
Transformer noise control is a systematic engineering task involving multiple disciplines such as electromagnetic design, mechanical structure, and acoustic engineering. By adopting an integrated approach of "source reduction — transmission blocking — system optimization," combined with condition monitoring and preventive maintenance, dual objectives of equipment safety and environmental protection can be achieved, providing technical support for building a greener power grid.