Vibration analysis and balancing of rotor blades

Imbalance on the rotor side is often the cause of increased strain in wind turbines. Imbalance also causes delay of start-up.

The cause of the imbalance in rotor may be for instance loose or missing trim weights, water collections inside the blade, collections of loose glue resin in the blade tip or ice attachments. Also the repair of one or more rotor blades can lead to significant changes of mass e.g. the movement of the centre of gravity on the other side of the blades.

To ensure problem-free and reliable operation of your wind turbines the balancing quality of rotor blades must be inspected, especially after repairs. If the rotor shows indications of being out of balance, the blades must be balanced.

A particular advantage is that the measuring and repairs go hand-in-hand, so the client can be sure that his wind turbine works without problems after repairs.

We have a measuring system at our disposal which enables us to register and process the low frequency vibrations in the blade. All necessary process values are measured with acceleration sensor, interpreted with data collector and analysed with specific software. This software provides all necessary details to statically balance the rotor.

Measuring is carried out during the rotation. Opposite to previous common balancing methods (e.g. weighing of the rotor blades) the measurements during rotation offer very accurate results.