Modelling of surface-mounted permanent magnet synchronous machines with stator faults

Rotating electrical machines play a very important role in the world's industry. Among them, the permanent magnet synchronous machines are more and more used because of their high power to weight ratio, their great efficiency and the recent affordability of magnet materials. Permanent magnet synchronous machines are also more and more envisaged in high power applications (railway applications for instance). In this context, these machines can be submitted to external and internal stresses, and degradation can occur in their electrical and mechanical parts. The adoption of permanent magnet synchronous machines in applications such as electric propulsion has been hindered by concerns about special risks posed by short-circuit faults in these machines. This is why industry is interested in adopting monitoring and diagnosis techniques to assess and evaluate condition of these machines. The modelling of surface-mounted permanent magnet synchronous machines with stator faults takes place in this context. A rich and flexible model of surface-mounted permanent magnet synchronous machines with stator faults is proposed here. A coupled magnetic circuits approach is used and very few restrictive assumptions are made. All parameters are calculated from the actual geometry and winding layout of the machines rather than from transformed or equivalent variables. The detailed depiction of the procedure needed to implement this model with simulation results is the subject of this paper.