Displacement Estimation Using Data Fusion Technique for Wind Turbine Tower Structures

Abstract

Wind energy industry has been developing rapidly owing to the relatively high reliability, good infrastructures and cost competitiveness of wind energy systems to the fossil fuels. Advances have been made to enhance the power efficiency of wind turbines and to reduce the levelized cost of energy while less attention has been focused on structural integrity assessment of structural sub-systems such as towers and foundations. Very recently higher tower technologies become more important to support larger wind turbines such as 10 MW turbines and also to enhance the wind quality and provide wind power nationwide (US DOE 2015). New concepts of wind towers such as concrete towers (Grunberg et al. 2013), composite towers with steel and concrete (Han et al. 2015), and modular towers are being developed for allowing turbine hub heights to cost effectively increase up to 140 m and higher. Accordingly, the maintenance technologies including structural integrity assessment for these new wind towers become much more essential to guarantee the structural serviceability and safety to support wind turbines. Among many parameters for structural integrity assessment, the most perceptive parameter may be the induced horizontal displacement at the hub height although it is very hard to measure particularly in large-scale and high-rise wind turbine structures. This study proposes an indirect displacement estimation scheme based on the cowind turbines and to reduce the levelized cost of energy while less attention has been focused on structural integrity assessment of structural sub-systems such as towers and foundations. Very recently higher tower technologies become more important to support larger wind turbines such as 10 MW turbines and also to enhance the wind quality and provide wind power nationwide (US DOE 2015). New concepts of wind towers such as concrete towers (Grunberg et al. 2013), composite towers with steel and concrete (Han et al. 2015), and modular towers are being developed for allowing turbine hub heights to cost effectively increase up to 140 m and higher. Accordingly, the maintenance technologies including structural integrity assessment for these new wind towers become much more essential to guarantee the structural serviceability and safety to support wind turbines. Among many parameters for structural integrity assessment, the most perceptive parameter may be the induced horizontal displacement at the hub height although it is very hard to measure particularly in large-scale and high-rise wind turbine structures. This study proposes an indirect displacement estimation scheme based on the co1