[show abstract][hide abstract] ABSTRACT: In view of the limitations of the condition monitoring (CM) techniques nowadays available for wind turbines (WTs), a fully intelligent condition monitoring technique has been developed in this paper using Empirical Mode Decomposition (EMD). The EMD method is characterized by its powerful capability in processing non-stationary and nonlinear signals and by being an efficient sifting algorithm. The effectiveness and the merits of the proposed technique in wind turbine condition monitoring have been experimentally validated on a Wind Turbine Condition Monitoring Test Rig.
[show abstract][hide abstract] ABSTRACT: Monitoring the condition of doubly-fed induction generators (DFIG) is growing in importance for Wind Turbines. This study presents the results of a comparison of DFIG steady state stator line current and instantaneous power when used as a means for generator condition monitoring, based on an examination of their frequency spectrum. For the purpose of this work, a detailed analytical model that makes it possible to simulate DFIG operation under a range of supply and winding balanced/ unbalanced operating conditions, was developed. Additionally, a purpose-designed DFIG test rig was built to facilitate the experimental validation of model results. The faulty machine current and power spectra are compared using experimental and model results.
[show abstract][hide abstract] ABSTRACT: Some large grid connected wind turbines use a low-speed synchronous generator, directly coupled to the turbine, and a fully rated converter to transform power from the turbine to mains electricity. The condition monitoring and diagnosis of mechanical and electrical faults in such a machine are considered, bearing in mind that it has a slow variable speed and is subject to the stochastic, aerodynamic effects of the wind. The application of wavelet transforms is investigated in the light of the disadvantages of spectral analysis in processing signals subject to such stochastic effects. The technique can be used to monitor generator electrical and drive train mechanical faults. It is validated experimentally on a wind turbine condition monitoring test rig using a three-phase, permanent-magnet, slow-speed, synchronous generator, driven by a motor controlled by a model representing the aerodynamic forces from a wind turbine. The possibility of detecting mechanical and electrical faults in wind turbines by electrical signal and particularly power analysis is heralded.
IET Renewable Power Generation 04/2009;
Wenxian Yang added a full-text to this article and 2 others.