Rotor imbalance of wind turbines: Detect and Adjust
Optimal operation of wind turbines: correct rotor adjustment and balancing!
Rotor imbalances may have different origins. They can be caused either by an uneven distribution of the rotor mass, called mass imbalance, or by deviations of the aerodynamic properties of the blades, such as blade angle deviations between the individual blades, called aerodynamic imbalance.
The individual blade angles of the three blades are examined in order to identify and quantify relative deviations among the three blades. This has impact on the energy production and on the life time though increased vibration.
According to our measurements, already relative blade angle differences of more than 0.3° lead to significant aerodynamic imbalance.
In addition, there may be a significant deviation of the blade angle setting from the design blade angle impacting on energy production.
The measuring system we use is the Plug-and-Use Balancing Box. It checks the wind turbines for rotor imbalance by vibration measurements. Individual measuring conditions are specified for each wind turbine type and configuration in order to assure comparable measurement results. The on-site evaluation of the measurements includes a comparison of the measured vibration level with specified limit values.
If an intolerable rotor imbalance is detected, a detailed measurement is recommended to reduce rotor imbalance according to the individual root cause.
Blade angles are determined with a well-proven photo-optical measuring method and statistical evaluation to assure result quality.
Our services:
- Rotor balancing
- Vibration measurements
- Blade angle measurements
- Onsite evaluations
- Root cause analyses