Triaxial Smart Sensor Based on the Advanced Analysis of Stray Flux and Currents for the Reliable Fault Detection in Induction Motors

The most recent trend in the electric motor condition monitoring area relies on combining the information obtained from different machine quantities in order to reach a more reliable conclusion about the motor's health. This knowledge is of critical importance nowadays, especially in industrial applications in which unexpected outages can lead to severe repercussions. This paper presents a new intelligent sensor that combines, in a single unit, the information obtained from the analysis of different quantities. In its current version the diagnostic provided by the sensor is obtained from the analysis of stray fluxes (both axial and radial) and currents. Unlike other solutions, the sensor is based on the application of advanced signal processing tools that are adapted to the analysis of these quantities under transient conditions. The combination of these new tools with the classical steady-state analysis of such quantities enables to obtain a more reliable conclusion on the motor health. The experiments included in the paper demonstrate the reliability provided by the sensor, which is being prepared to incorporate a third input based on infrared data.