Detection and Phase Identification of Interturn Faults in the Stator and Rotor of Doubly-Fed Induction Generators Using Negative-Sequence Currents

A method for stator and rotor interturn fault detection, and phase identification, is proposed using the negative-sequence currents of the Doubly-Fed Induction Generators. The stator and rotor currents are measured and filtered to determine the root-locus of the dq negative-sequence current, which is used to distinguish between healthy and faulty conditions, and identifying the stator or rotor phase under fault. The method is tested with experimental data, and it is able to detect faults under different speeds and torque.