CIGRE Croatia Paper Practical Application of Electrical and Current Signature Analysis in DFIG Turbine Systems Oct 14 2025

Abstract—On and off-shore wind generators and powertrain systems have significant reliability concerns that increase the operations and maintenance costs associated with ownership and affect individual tower availability. The primary failure points in DFIG (Doubly-Fed Induction Generators) include: the bearings, stator wedges, and rotor wye-rings in the generator; bearings and gears in the gearbox; and, lubrication and electrical discharge defects in main bearings. These conditions and associated degradation of components have been evaluated with electrical and current signature analysis techniques since 2003, with emphasis for early detection of stator wedge and rotor wye ring failures since 2017. Electrical Signature Analysis necessary to provide spectral analysis using either expert or ML/AI systems to determine classification and severity of degradation. The air gap of the generator is used as the transducer for the measurement of conditions throughout the system. In this paper and presentation we will discuss the technology, application and results including some of the identified root causes associated with these defects.