Continuous dynamic monitoring of an onshore wind turbine

Abstract Current utility-scale wind turbines are highly dynamic systems excited by a large variety of loading sources. The proper operation of wind turbines thus requires a complete knowledge of the actual dynamic behavior of the system, in order to ensure the expected longevity of their main structural elements. In that context, this paper describes the monitoring project developed for a 2.0 MW wind turbine, the description of the installed monitoring system, as well as the main steps included in the methodology developed for the continuous processing of the collected data. The main results achieved during one year of monitoring are shown in detail. They allowed to accurately characterize the variability of the dynamic properties of the wind turbine, with special emphasis on the natural frequencies and damping ratios of the most important vibration modes, throughout normal operating conditions of the turbine. In addition, several shutdown events were identified and used to estimate the modal damping of the wind turbine through the analysis of free-decay responses of the structure. This monitoring project contributes to improve the knowledge on the dynamic behavior of onshore wind turbines under normal operating conditions.

[1]  Jingyan Wu,et al.  A new multibody modelling methodology for wind turbine structures using a cardanic joint beam element , 2007 .

[2]  Filipe Magalhães,et al.  Online automatic identification of the modal parameters of a long span arch bridge , 2009 .

[3]  Halil Ceylan,et al.  A survey of health monitoring systems for wind turbines , 2015 .

[4]  María Isabel Blanco.  The economics of wind energy , 2009 .

[5]  Patrick Guillaume,et al.  Structural health monitoring of offshore wind turbines using automated operational modal analysis , 2014 .

[6]  Richard A. Johnson,et al.  Applied Multivariate Statistical Analysis , 1983 .

[7]  Guido De Roeck,et al.  System identification and modal analysis in structural mechanics , 2012 .

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

[9]  Dmitri Tcherniak,et al.  Applicability Limits of Operational Modal Analysis to Operational Wind Turbines , 2011 .

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

[11]  Filipe Magalhães,et al.  Damping Estimation Using Free Decays and Ambient Vibration Tests , 2010 .

[12]  Patrick Guillaume,et al.  The dynamics of an offshore wind turbine in parked conditions: a comparison between simulations and measurements , 2015 .

[13]  Sebastian Thöns,et al.  Vibration-based structural health monitoring of a wind turbine system. Part I: Resonance phenomenon , 2015 .

[14]  Filipe Magalhães,et al.  Development and implementation of a continuous dynamic monitoring system in a wind turbine , 2016, Journal of Civil Structural Health Monitoring.

[15]  P. Guillaume,et al.  The PolyMAX Frequency-Domain Method: A New Standard for Modal Parameter Estimation? , 2004 .

[16]  Mayorkinos Papaelias,et al.  Condition monitoring of wind turbines: Techniques and methods , 2012 .

[17]  Filipe Magalhães,et al.  Explaining operational modal analysis with data from an arch bridge , 2011 .

[18]  Daniel Rixen,et al.  Operational modal analysis of a 2.5 MW wind turbine using optical measurement techniques and strain gauges , 2013 .

[19]  B. Peeters,et al.  Reference based stochastic subspace identification in civil engineering , 1999 .

[20]  Anand Natarajan,et al.  Identification of support structure damping of a full scale offshore wind turbine in normal operation , 2015 .