Condition monitoring of wind turbine for rotor fault detection under non stationary conditions

Abstract

Condition monitoring of Wind Turbine based induction generators still faces challenges due to their operation in harsh and aggressive environments. The detection of anomalies at an initial stage is necessary for reducing the downtime of Wind Turbines. Depending on wind speed, the wind turbine generator operates continuously in non-stationary conditions. Under non-stationary conditions, the rotor fault frequency components present at generator output spreads out on bandwidth proportional to the speed which complicates its detectability. Therefore, this paper proposes a potential approach based on the use of wavelet analysis for diagnosing rotor eccentricity fault using WTG electrical signals. Its effectiveness under speed and load varying conditions is validated by experiments on a wind turbine condition monitoring test rig. The effectiveness of the setup was benchmarked with already proven WT test rigs. Keywords: Wind turbine emulator, Non-stationary signals, Self excited induction generator (SEIG), Wavelet decomposition, Fault diagnostics, Condition monitoring, Wind Turbine Generator (WTG)