Structural Dynamics Analysis and Model Validation of Wind Turbine Structures

The focus of this paper is the development of validated structural models of wind turbine structures and their substructures. A typical modern wind turbine is a large structure composed of a single tower, a nacelle located atop the tower which houses the drive train mechanical components, and three rotor blades. In very broad terms, a wind turbine design team must consider the dynamic response of the full system in the design process along with detailed design for each individual substructure. Blades are a critical substructure of a wind turbine as they carry large loads in capturing the energy from the wind, and must be designed to maximize performance and reliability while minimizing their cost. The work summarized in this paper has two major parts. First, we discuss the structural dynamics analyses that are performed to design a modern wind turbine structure. Secondly, a methodology for validating blade structural models is presented. A number of blades incorporating innovations for large blade technologies have been designed and tested at Sandia National Laboratories in recent years. Results from recent tests and validation of models for these blades will be presented. I