During the long-term operation of wind turbines, blade vibration is an issue that cannot be ignored. As the core component of a fan, blades bear the impact of airflow, centrifugal force, gravity, and occasional eddy currents. If the vibration is not effectively controlled, it may lead to a decrease in equipment efficiency, reduced operational stability, and even affect the overall lifespan of the machine. Therefore, how to scientifically and accurately control blade vibration has become a continuous focus of attention for various wind turbine users and manufacturing enterprises.

1、 Common causes of fan blade vibration

Changes in aerodynamic load: Wind speed, airflow direction, and pressure fluctuations can all cause uneven force distribution on the blades.

Insufficient structural stiffness: During the design or manufacturing phase, if the blade structure stiffness is relatively low, it can lead to significant deformation during operation.

Coupling between rotational speed and natural frequency: When the rotational speed approaches the natural frequency of the blade, it is easy to cause resonance, leading to a sharp amplification of vibration.

Long term operational fatigue: After prolonged operation, the blades may experience local fatigue and small cracks, which may also exacerbate vibration.

2、 Common blade vibration control methods

Structural optimization design: In the initial stage of blade design, improve overall stability through finite element analysis and aerodynamic simulation.

Dynamic balance and testing: Regularly adjust the dynamic balance of the fan rotor to reduce unbalanced torque.

Flexible connection and support improvement: By adjusting the elastic support or damping material of the connection part, the absorption capacity of vibration is improved.

Online monitoring system: Utilizing sensors to collect real-time vibration data, facilitating rapid detection and processing of anomalies.

3、 The function of Tuned Mass Damper (TMD)

Tuned Mass Damper (TMD) is an important vibration control device widely used in high-rise buildings, bridges, and rotating machinery. The application of TMD on wind turbine blades has the following significant effects:

Reduce resonance effect

The core principle of TMD is to add a specific frequency of additional mass to the blade structure, and to cooperate with springs and damping elements to produce reverse resonance with the natural frequency of the blade, thereby effectively weakening the vibration amplitude.

Improve operational stability

The blades equipped with TMD perform more smoothly under different speed conditions, which helps to reduce the dynamic impact caused by uneven airflow and improve the continuity and stability of fan operation.

Extend service life

When the vibration amplitude decreases, the stress at the root of the blade decreases, and the fatigue accumulation effect of long-term operation is delayed, which helps to extend the life of the whole machine and blades.

Easy to maintain and upgrade in the later stage

Compared to structural reinforcement, TMD devices often have a higher degree of modularity, are easy to maintain in the later stage, and can be fine tuned according to actual operating conditions.

4、 Insights from Enterprise Practice

In recent years, our company has undertaken multiple large-scale wind turbine projects. Our technical team has effectively controlled blade vibration under different wind speed conditions by introducing tuned mass damper parameters in the blade design stage and combining them with a real-time vibration monitoring system. This not only optimizes the overall performance of the fan, but also reduces maintenance costs for customers in the later stage.

V. Conclusion

Fan blade vibration control is a systematic work that requires both design optimization at the source and scientific maintenance and monitoring in the later stage. As a mature vibration suppression method, tuned mass dampers have been proven to have good effects in practical applications. For wind turbine manufacturers and users, adopting this technology reasonably can not only improve equipment operation stability, but also accumulate technological advantages in fierce market competition.