Geometric rotor angle measurement

We use a laser-based measurement procedure to check the dynamic and aerostatic behaviour of the rotor and the entire plant. As part of the procedure, we scan two sections of the rotor blade profiles and measure tower oscillations in the wind direction. We use high-resolution, high-precision laser sensors for our measurements and a special software for analysing the measurement results. Measurements are carried out under real-life conditions while the power plant is in operation. The results are directly available, i.e. immediately after the procedure has been completed, and show any offset or misalignment of rotor blades.

An “EWS Performance Check” carried out bei Energiewerkstatt Consulting GmbH for Windkraft Simonsfeld AG confirms that it pays off to have any misalignment of rotor blades corrected: Energiewerkstatt Consulting GmbH determined output curves by means of ground-based LIDAR measurements before and after the correction of rotor blade angles. A comparison of the two output curves showed that, in case of a misalignment of only 3 degrees, the output was reduced by more than 2 percent. Depending on the misalignment, type and location of the wind turbine, measurements and any corrections which may be necessary will pay off within a few months.

In addition to higher outputs, corrections have another important advantage: rotor blade misalignments result in undesired oscillations, subject drivetrains to strain and will, sooner or later, cause damage. In extreme cases, they may even result in a reduction of a wind power plant’s service life.