How much energy a wind turbine produces depends not only on the wind, but also on the condition of the rotor blades. At present, the plants still have to be decommissioned in order to be able to carry out a status assessment. “Of course, this leads to high downtime costs for maintenance,” says Friederike Jensen from the Bremen Institute for Measurement Technology, Automation and Quality Science (BIMAQ – Bremer Institut für Messtechnik, Automatisierung und Qualitätswissenschaft) at the University of Bremen. She heads up the recently launched AutoFlow research project. It deals with the question of how the condition of the rotor blade can be recorded and evaluated during turbine operation – or in the truest sense of the word “on the fly.”

“For the first time, aircraft systems equipped with numerous sensors are being used that can carry out both thermographic and laser-based measurements,” says the engineer, commenting on the new approach. “With the experience and results of this project, we hope not only to significantly reduce maintenance costs for plant operators, but also to increase operational reliability – because we can detect and repair potential damage at an early stage.”

Automated Flight System for Onshore and Offshore Measurements

The project even goes one step further: the unmanned flight system should not only be able to be controlled remotely, but also carry out measurements completely automatically at nearby wind turbines. “A particular challenge in the development of the automated flight system is the harsh environmental conditions in the offshore sector,” explains Tim Reuscher, Head of Mobility at the Institute of Automatic Control at RWTH Aachen University. At the same time, the data should be transmitted and evaluated in real time in order to obtain a quick initial overview of the state of the plant on-site. This makes it possible to decide directly which areas of the plant require a separate investigation.

Close Cooperation between Science and Industry

The project is led by the BIMAQ (Institute Director Professor Andreas Fischer), which is responsible for the coordination and the measurement technology to be installed on the flight system. The flight system and hangar, which must be well suited for harsh offshore conditions, are developed by Copting GmbH, with software support provided by Oecon GmbH. The Institute of Automatic Control (irt  – Institut für Regelunstechnik) at RWTH Aachen University is responsible for the development of the control of the flight system and its trajectories as well as for the control of the measurement routine during flight.

In addition, the research project is supported by the OFFSHORE-WINDENERGIE Foundation and Deutsche WindGuard with regard to the definition of (measurement) requirements and the validation of the flight-based measurement system. WindMW, as an offshore wind farm operator, is supporting the development and offshore demonstration of the flying measuring system in the offshore wind farm off Heligoland.

The AutoFlow project will receive 1.8 million euros in funding from the German Federal Ministry for Economic Affairs and Climate Action for a period of three years.

Contact:

Friederike Jensen (MSc)
Working Group on Energy Systems and Materials Testing
University of Bremen – Faculty 4 Production Engineering 
Bremer Institute for Measurement Technology, Automation and
Quality Science (BIMAQ)
Tel.: +49 421 218-64664
Email: f.jensen@bimaq.de