Reduced Thermal Model of an Induction Machine for Real-Time Thermal Monitoring

An electric machine submitted to dissipations and a too high temperature can generate irreversible damage. A reduced thermal model allows us to monitor the critical points of the machine. The thermal modeling of the machine adopted here results from the association of two methods: a nodal approach which models the diffusion in the structure and a computational fluid dynamics (CFD) approach which characterizes the convective heat exchanges which operate in the end cavities. A methodology of reduction is proposed and applied to the thermal model of a 5.5-kW two-pole induction machine to obtain a reduced four-node model for real-time thermal monitoring.