Rotor blade inspection and lightning protection measurements by drone on wind turbines - more efficient inspections

The main problems with wind turbine maintenance and inspection are the high cost and inefficiency of traditional methods. Typically, two teams are required to fully inspect a wind turbine: one to inspect the machine and another to inspect the blades. This approach is not only costly but also time consuming. In addition, conventional methods of lightning protection testing often produce inaccurate results. Damage is difficult to locate, which calls into question the effectiveness of the entire maintenance operation. This mismatch between cost and quality of results is a significant burden for many operators. 

The solution: 

An innovative lightning protection process, developed in collaboration with Sulzer Schmid, has been in use since 2022. The technology makes it possible to fully image the surface of rotor blades of any size in a very short time. High-resolution imaging and a wide detection field ensure a significantly higher defect detection rate. A key advantage of this process is the autonomous flight pattern of the drones, combined with an initial image analysis based on artificial intelligence. The final evaluation of the images is carried out by rotor blade experts, representing an intelligent symbiosis of technological innovation and human expertise. 

Enertrag has developed an innovative solution to meet these challenges: 2in1 LPS Inspection. This method combines rotor blade inspection and lightning protection testing in a single process, without the need for rope access techniques. In the last 12 months, over 350 wind turbines have been successfully inspected using this technology.

 Benefits of 2in1 LPS inspection

 The next generation of wind turbines is reaching new heights and dimensions, with hub heights of well over 150 metres and rotor diameters of up to 160 metres. Traditional inspection methods, such as rope access, are reaching their limits for both safety and cost reasons. Enertrag has therefore turned to the use of specialised drones to inspect these gigantic turbines efficiently and safely. Thanks to this technology, the size of the wind turbine or the length of the rotor blades no longer matter.

• Increased efficiency in inspection and route planning: The use of specialised drones and improved lightning protection significantly reduces turbine downtime, resulting in financial savings.
  
• High resolution imaging and wide field of view: These technological advances significantly increase fault detection rates.
  
• Realistic lightning testing: Enertrag Operation measures at 6000V, which is much closer to a real lightning strike than the 24V previously used.
  
• This robust measurement method not only meets the legal requirements of operators and insurers, but also offers significantly improved safety for the systems.
  
• Smart symbiosis of drone technology and expert knowledge: The combination of state-of-the-art technology and inspectors' years of experience in assessing defects and classifying inspection data maximises the efficiency and accuracy of inspections.
  
• Weather resilience and predictability: The drones used can fly in wind speeds of up to 10 m/s and in very cold temperatures, improving the predictability of inspections.
  

 Implementation and results

The implementation of 2in1 LPS Inspection on more than 350 wind turbines has shown that this method not only offers theoretical advantages, but also convinces in practice. The combination of cost efficiency, time savings and increased safety makes 2in1 LPS Inspection a valuable tool for wind turbine operators. 

Conclusion and outlook 

With the introduction of the 2in1 LPS Inspection and the use of advanced technologies such as specialised drones and a new lightning protection method, Enertrag is setting new standards in wind turbine inspection. These innovations not only enable more efficient and accurate inspections, but also help to reduce costs and increase the safety and longevity of the turbines. The benefits of these technologies are a clear sign that the wind energy industry can continue to grow efficiently and sustainably thanks to innovative solutions such as Enertrag's 2in1 LPS inspection. 

The accompanying video explains the problem in detail, as well as the functionality and benefits of the 2in1 LPS Inspection.