Wind turbine condition monitoring using generator control loop signals

This paper presents an advanced monitoring and diagnosis method for detecting of incipient electrical and mechanical faults in a wind-turbine-driven doubly-fed induction generator (DFIG). In this application, the stator windings are directly connected to the grid, whereas a converter controls the rotor currents by means of a Field Oriented Control (FOC) scheme. A new diagnostic method, based upon frequency analysis of the dq rotor current error signals inside the machine-side converter controller, is proposed. Simulation results confirm that the spectra of these signals have features that are suitable for an effective diagnostic procedure. The proposed system could be embedded in a wind turbine at very low cost.