Public Libraries of Suffolk County, New York

Evaluation of the new B-REX fatigue testing system for multi-megawatt wind turbine blades, preprint, D. White, W. Musial, and S. Engberg

eng

federal national government publication

no index present

humor satires etc

Evaluation of the new B-REX fatigue testing system for multi-megawatt wind turbine blades

electronic resource

dictionaries

D. White, W. Musial, and S. Engberg

Conference paper, NREL/CP-500-37075

preprint

The National Renewable Energy Laboratory (NREL) recently developed a new hybrid fatigue testing system called the Blade Resonance Excitation (B-REX) test system. The new system uses 65% less energy to test large wind turbine blades in half the time of NREL's dual-axis forced-displacement test method with lower equipment and operating costs. The B-REX is a dual-axis test system that combines resonance excitation with forced hydraulic loading to reduce the total test time required while representing the operating strains on the critical inboard blade stations more accurately than a single-axis test system. The analysis and testing required to fully implement the B-REX was significant. To control unanticipated blade motion and vibrations caused by dynamic coupling between the flap, lead-lag, and torsional directions, we needed to incorporate additional test hardware and control software. We evaluated the B-REX test system under stable operating conditions using a combination of various sensors. We then compared our results with results from the same blade, tested previously using NREL's dual-axis forced-displacement test method. Experimental results indicate that strain levels produced by the B-REX system accurately replicated the forced-displacement method. This paper describes the challenges we encountered while developing the new blade fatigue test system and the experimental results that validate its accuracy