BeBen XXL: Accelerated experimental endurance strength verification for large wind turbine components on the example of main shafts

The aim of the fatigue tests is not only to damage the specimen, rather it is important to reproduce a realistic loading and thus wear and tear as occur in operational wind turbine main shafts. For this reason we have conducted a detailed analysis of simulated and measured load time series for the main shaft. After processing the data using the „Rain-Flow-Counting“ method, lifetime damage was calculated based on Miner‘s rule. An important output of those analyses is the information on which degrees of freedom are relevant for fatigue damage mechanisms and thus helping us to design an adequate test bench.

The project‘s major aims can be summarized as:

• Comparison of theoretical and experimental endurance strengths
• Adjustment of certification guidelines
• Material savings

Some highlights of the project scope:

• Material tests (s-n curve, impact test)
• Development and acquisition of a main shaft fatigue test bench
• Full scale main shaft fatigue tests