Virtual Sensing For Wind Turbine Blade Full Field Response Estimation In Operational Modal Analysis

Abstract

The inaccessibility of wind turbine components after their installation and the stochastic nature of the excitation they are subjected to, render their dynamic behavior challenging for investigation. Wind turbine blade manufacturers are required to carry out extensive test campaigns on each single blade individually prior to proceeding with commercialization. Static and fatigue tests are usually performed on prototypes in order to ensure that each blade can stand extreme loads, even after being subjected to high cyclic loading. The same instrumentation used for static and fatigue tests can be adopted for performing Operational Modal Analysis with the purpose of identifying the blade modal parameters, which can help analyzing failure modes and system stability problems. Measurements performed during tests are usually acquired at accessible locations and with a limited number of sensors due to their high cost. This work focuses on providing alternatives to costly and impractical physical measurements on wind turbine blades by combining information from cost-effective simulated models and more realistic test data through the so-called Virtual Sensing techniques, e.g., Kalman-type filters and Modal Expansion methods. © The Society for Experimental Mechanics, Inc. 2022