Stator fault diagnosis by reactive power in dual three-phase reluctance motors

Electrical machines are wide spread because of their intrinsic robustness, versatility and reduced impact on energy and resources. Recently, the demand has focused on specific features: compatibility with power converters and fault tolerance. In fact, a wide range of applications require variable speed drives and high rejection of faults, i.e. safe operation also for non-critical applications. Here, a dual three-phase stator configuration is used, and a novel method for stator fault detection is presented. This method is based on reactive power measurements from both three-phase systems. A differential diagnostic index is defined, that can be used to detect effectively stator faults, isolating them from torque oscillations, load unbalances or other pitfalls.