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Competence Center for Wind Energy


The so-called Competence Center for Wind Energy (CCW) is being constructed on the premises of PTB.

Competence Center for Wind Energy at PTB: a) Coordinate measuring machine b) Wind tunnel for calibration of wind Lidar systems c) Torque standard machine

Its technical focal points are a large coordinate measuring machine with a measuring volume of 5 m × 4 m × 2 m; a torque standard machine (Dm- NME) for traceability of torques of up to 5 MN ∙ m (expandable to 20 MN ∙ m); and a system for calibration of wind Lidar systems. This center, the only one of its kind in the world, will be used to conduct research on and implement new measuring wind energy systems (WES). At the same time, PTB’s service offer is being considerably expanded.

Coordinate metrology

The goal of constructing the CCW is to ensure reli- able, high-precision measurements of large compo- nents (especially large gear components for WES) for the first time ever and in a sustainable way. As planned, the large coordinate measuring machine that has three moveable Cartesian axes will also be equipped with a rotary table. It is particularly sui- table for measuring rotationally symmetrical com- ponents such as gears, rotor/stator components and bearing rings. Furthermore, the use of traceable laser interferometers allows the measurement accu- racy of the system to be markedly improved when compared to commercial coordinate measuring machines. In this way, the geometrical errors of this measuring machine and the deformations caused by temperature effects can be better compensated for. For example, in the future, the anticipated measure- ment uncertainty for components with a diameter of 4 m will be better than 10 μm.

Torque measuring technology

The construction of the new Dm-NME will allow the world’s first traceable torque measurements of up to 5 MN ∙ m to be performed. This, in turn, will make it possible to calibrate corresponding torque transfer transducers for industrial applications. The system is being developed and constructed by PTB. An important focus is on research – specifically, on the metrological investigation of issues related to enhancing WES to achieve even higher levels of performance of up to 20 MN ∙ m. For example, the system will also enable bending moments, axial forces and dynamic excitations of up to 3 Hz, thereby making it possible for the first time to realize a metrological characterization of dynamic influences in the (MN ∙ m) torque range, as well as in the MN force range. These simultaneous loads will allow multicomponent transducers to be calibrated in a trace- able and practice-oriented way for force and torque.

Wind tunnel measuring device

The wind tunnel measuring device will allow the first systematic investigations to take place for the validation of a novel Lidar remote measurement procedure. To do so, the uncertainty budget of the bistatic wind Lidar system for wind speed measurements (developed by PTB as a transfer standard) will be analyzed thoroughly at a very high spatial resolution and accuracy in the wind tunnel measuring device. By doing so, it will fulfill the strict requirements placed on calibration facilities concerning the quality of the flow generated and concerning the metrological traceability of the flow velocity using a laser Doppler anemometer as a reference standard.

German companies will benefit considerably from the construction of the CCW. By means of the calibrated standards and transducers, they will be able to perform the first traceable evaluations and improvements of their own manufacturing processes, and to demonstrate the quality of their products on the competitive international market. The German Federal Ministry for Economics and Energy is sponsoring the purchase and construction of the measuring systems and the hiring of scientific personnel with funding amounting to around 9.4 million euros. In addition, new buildings will be constructed and new infrastructural measures set up with funds from the budget of PTB. These systems will be operated jointly by Departments 1 and 5.