Development of a low cost test rig for standalone WECS subject to electrical faults

- The proposed methods in this research allow continuous real-time tracking of stator faults in WTG operating under continuous stationary and non-stationary conditions.
- Stator winding fault can be successfully detected in normal IM using FFT analysis whereas in the case of WTG, due to variations in wind speed and hence slip variations, fault frequency components are not visible in FFT spectrum.
- For condition monitoring of wind turbine, a low-cost WTE setup is designed and developed. The designed WT test rig follows the power curves of WT characteristics. The result shows a very good operation in the whole operating range of the SCIG and due to its simplicity, real-time interfacing, and control for monitoring -it is suitable for practical use.

In this paper, a contribution to the development of low-cost wind turbine (WT) test rig for stator fault diagnosis of wind turbine generator is proposed. The test rig is developed using a 2.5 kW, 1750 RPM DC motor coupled to a 1.5 kW, 1500 RPM self-excited induction generator interfaced with a WT mathematical model in LabVIEW. The performance of the test rig is benchmarked with already proven wind turbine test rigs. In order to detect the stator faults using non-stationary signals in self-excited induction generator, an online fault diagnostic technique of DWT-based multi-resolution analysis is proposed. It has been experimentally proven that for varying wind conditions wavelet decomposition allows good differentiation between faulty and healthy conditions leading to an effective diagnostic procedure for wind turbine condition monitoring.