Online DWT algorithm for identification of aerodynamic damping in wind turbines

Abstract A new online identification method for estimating the time-varying aerodynamic damping of a wind turbine is proposed. Through a combination of measured aeroelastic response data and an aeroelastic wind turbine model, the time-varying aerodynamic damping matrix can be identified with the aid of the real-time Discrete Wavelet Transform (DWT) technique. The proposed method is validated by means of a 13-DOF aero-servo-elastic wind turbine model, which is used to mimic the in situ aeroelastic response of the NREL 5 MW wind turbine. A measurement noise sensitivity survey is conducted. Results from current DWT-based estimation method are compared with those from previously proposed Continues Wavelet Transform (CWT)-based estimation method and found to be superior in terms of accuracy and efficiency.

[1]  Patrick Guillaume,et al.  Experimental and computational damping estimation of an offshore wind turbine on a monopile foundation , 2013 .

[2]  Søren Nielsen,et al.  Dynamics and Control of Lateral Tower Vibrations in Offshore Wind Turbines by Means of Active Generator Torque , 2014 .

[3]  Mahmoud El-Kafafy,et al.  Monitoring resonant frequencies and damping values of an offshore wind turbine in parked conditions , 2014 .

[4]  Morten Hartvig Hansen,et al.  Two methods for estimating aeroelastic damping of operational wind turbine modes from experiments , 2006 .

[5]  Brian Ray Resor,et al.  Aeroelastic Instability of Very Large Wind Turbine Blades. , 2012 .

[6]  Scott Schreck,et al.  Wind Tunnel Testing of NREL's Unsteady Aerodynamics Experiment , 2001 .

[7]  Biswajit Basu,et al.  A padding method to reduce edge effects for enhanced damage identification using wavelet analysis , 2015 .

[8]  B. Basu,et al.  On equivalent linearization using wavelet transform , 1999 .

[9]  Søren Nielsen,et al.  Real-time hybrid aeroelastic simulation of wind turbines with various types of full-scale tuned liquid dampers , 2018, Wind Energy.

[10]  B. Petersen,et al.  A method for determination of damping for edgewise blade vibrations , 2000 .

[12]  Ingrid Daubechies,et al.  Ten Lectures on Wavelets , 1992 .

[13]  Biswajit Basu,et al.  Performance evaluation of full-scale tuned liquid dampers (TLDs) for vibration control of large wind turbines using real-time hybrid testing , 2016 .

[14]  Søren Nielsen,et al.  Identification of aerodynamic damping in wind turbines using time-frequency analysis , 2017 .

[15]  J. van der Tempel,et al.  Design of support structures for offshore wind turbines , 2006 .

[16]  M. Kühn.  Dynamics and design optimisation of offshore wind energy conversion systems , 2001 .

[17]  Andrew T. Myers,et al.  Aerodynamic Damping and Seismic Response of Horizontal Axis Wind Turbine Towers , 2014 .

[18]  Nestor A Agbayani.  A Technical Overview of ASCE/AWEA RP2011: Recommended Practice for Compliance of Large Land-based Wind Turbine Support Structures , 2014 .

[19]  Ajit R Godbole,et al.  Effects of aerodynamic damping on the tower load of offshore horizontal axis wind turbines , 2017 .

[20]  Martin Otto Laver Hansen,et al.  Aerodynamics of Wind Turbines , 2001 .

[21]  Morten Hartvig Hansen,et al.  Aeroelastic instability problems for wind turbines , 2007 .

[22]  Torben J. Larsen,et al.  Present Status of Aeroelasticity of Wind Turbines , 2003 .

[23]  Michael Muskulus,et al.  Decoupled simulations of offshore wind turbines with reduced rotor loads and aerodynamic damping , 2017 .