Multi-Physical Time- and Frequency-Domain Fault Detection and Isolation Technique for Power-Electronic Converters in DFIG Wind Turbines

A multiphysical time- and frequency-domain fault detection and isolation method for power-electronic converters of wind turbines is presented in this article, with focus on open-circuit faults in doubly-fed induction generator drivetrain topology. In order to reduce the risk of false alarms, the proposed approach combines fault indicators based on a time- and frequency-domain analysis of electrical signals, as well as a frequency-domain analysis of vibration signals. The effectiveness of the method is demonstrated via test bench data recorded under different healthy and faulty operating conditions.