Technical Note: Blade Integrated Overspeed Protection for Small Turbines — Experimental Observations
McMahon NM*, Rogers P, Byrne R, MacArtain P, Staudt LD.
Abstract: In the 1980s many wind turbines were stall-regulated fixed-pitch machines. The rotors were often equipped with blade-integrated overspeed protection such as ailerons, tip brakes and flip tips. The market for larger small wind turbines is reappearing, and it is conceivable that blade-integrated overspeed control will re-emerge as a solution. Although electrical braking techniques associated with permanent magnet generators are useful, independent rotor-based overspeed control mechanisms are at present still required for fail-safe operation. In this note, we present observations from more than twenty experimental tests. We note that it is possible to effect braking using particular leading-edge profiles.
* Corresponding author.
We'd like to thank Ronnie Owens of Meitheal na Gaoithe who provided us with much help over the course of the work presented here. The Institute for Numerical Computation and Analysis (INCA) also provided infrastructural support.