New Publication: Detecting Nonadjacent Demagnetisation in Direct-Drive PM Generators
We are excited to announce the publication of our latest research in IET Electric Power Applications, as part of the MEGA WAVE PTO project. This study introduces a novel method for detecting nonadjacent demagnetisation faults in direct-drive permanent magnet generators (PMGs), a critical step toward improving the reliability of renewable energy systems.
About the research
Direct-drive PMGs are widely used in wave, tidal, and wind energy systems due to their high efficiency, modularity, and low power consumption. However, nonadjacent demagnetisation — when two or more magnets fail in positions that are not next to each other — can lead to false negative diagnostic alarms with traditional monitoring methods like Motor Current Signature Analysis (MCSA).
This research demonstrates that magnetic flux-based diagnostics provide a more reliable approach for detecting these faults. The study combines numerical analysis and experimental testing to validate the method and improve confidence in condition monitoring for offshore renewable energy applications.
Key contributions
Introduces a diagnostic approach specifically for nonadjacent demagnetisation faults
Evaluates limitations of conventional monitoring techniques such as MCSA
Provides experimental and simulation-based validation
Supports the development of fault-tolerant, reliable PMGs for wave, tidal, and wind energy systems
Publication details
Title: Nonadjacent Demagnetisation Detection in Direct-Drive Permanent Magnet Generators for Renewable Energy Systems
Authors: Alexandros Sergakis, Giorgos A. Skarmoutsos, Markus Mueller, Konstantinos N. Gyftakis
Published in: IET Electric Power Applications (Open Access, 2025)
Read the full paper: https://doi.org/10.1049/elp2.70085
Why this research matters
Reliable detection of nonadjacent demagnetisation faults is essential for enhancing the safety, efficiency, and lifetime of permanent magnet generators in demanding offshore environments. The methods presented in this paper offer a foundation for improved fault-tolerant designs and contribute to advancing wave energy technology under the MEGA WAVE PTO project.
For more updates on our research, stay tuned to the News Section of the MEGA WAVE PTO website.
