The PTB Wind project set out to create a new metrological infrastructure that would sustainably support the wind‑energy sector. Three core disciplines were addressed: geometric measurement of drive‑train components (KMT), measurement of large torques (DM), and remote wind‑speed measurement using a novel LIDAR principle (LIDAR). The project’s overall goal was to establish a Kompetenzzentrum für Windenergie (CCW) that would house the PTB’s most important competencies in these areas under one roof, enabling the development of new measurement devices, application‑oriented methods, and realistic test bodies.

In the geometric‑measurement work package, a large‑coordinate‑measuring machine (Groß‑KMG) was designed with a measurement volume of 5 × 4 × 2 m³. This device allows the calibration of sizeable wind‑energy‑apparatus components, such as drive‑train shafts and linear guides, with high positional accuracy. The machine’s design incorporates laser‑tracking for real‑time verification of form and positional tolerances during alignment, ensuring that the tolerances of the linear guides meet the stringent requirements of modern wind‑turbine drives.

The torque‑measurement package delivered a torque‑normal measurement device (DM‑NME) capable of reproducing torques up to 5 MN·m, with a future extension to 20 MN·m envisaged. The device uses a hydraulic‑controlled actuator system that can generate the required torque while simultaneously measuring the resulting force and displacement. The system’s calibration procedure was validated against reference torque standards, demonstrating a measurement uncertainty below 0.5 % of the full scale for the 5 MN·m range. This capability is critical for testing the mechanical integrity of increasingly large wind‑turbine gearboxes and shafts.

The wind‑LIDAR work package focused on a wind‑tunnel measurement system (WKME) that validates a 3‑D wind‑LIDAR system developed by the PTB and calibrates commercial remote wind‑measurement systems. The WKME provides a controlled wind field with known velocity profiles, allowing the comparison of the remote LIDAR readings against ground‑truth data. The validation experiments confirmed that the PTB’s 3‑D LIDAR achieves a velocity measurement accuracy of better than 1 % across a range of wind speeds up to 20 m s⁻¹, meeting the requirements for offshore wind‑farm monitoring.

The project was carried out over an extended period, with several phases (AP 1–AP 6) that included design, procurement, manufacturing, and integration of the measurement devices. Delays due to late or incorrect component deliveries and COVID‑19‑related staff shortages required two project extensions, but the final installation of the Groß‑KMG, DM‑NME, and WKME was completed by mid‑2021. Subsequent calibration and validation campaigns have already been conducted, demonstrating the full operational readiness of the new infrastructure.

Collaboration was central to the project’s success. The PTB coordinated with specialized manufacturers for the casting and welding of large structural components, ensuring that the Groß‑KMG’s frame met the required dimensional tolerances. Partnerships with wind‑turbine manufacturers and research institutes provided access to drive‑train components and wind‑tunnel facilities for testing. The project was funded through a federal grant, enabling the construction of a dedicated building complex that houses the new measurement infrastructure. The PTB’s role encompassed project management, design, procurement, and integration, while partners supplied components, performed specialized machining, and contributed expertise in wind‑turbine mechanics and remote sensing. The resulting competence centre now offers a unique, world‑first metrological platform that supports the entire wind‑energy value chain, from component design to field‑level monitoring.