TRANSIENT STATE STUDY OF ELECTRIC MOTOR HEATING AND PHASE-CHANGE SOLID-LIQUID COOLING

This study reports on modelling of an autosynchronous electric motor s tator, operating at transient state. The developed model, of the nodal type, includes around 20 nodes. The simulations showed that hot spots are localized on the winding heads and led to the choice of a solid-l iquid phase change cooling system. The comparison between simulation a nd experiment permitted the identification of unknown parameters. The model gives a good accuracy during steady-state and in the rising temp erature phase. The modelling of the phase change cooling is realized b y the addition of two nodes. The sensitivity analysis to PCM propertie s shows that the hot spot temperature decreases with increasing conduc tivities, inertia and latent heat of melting of the PCM and with decre asing melting temperature. Gallium (metal melting at 30 degrees C) is the best PCM for the cooling of hot spots and P116 paraffin is the bes t non-metallic PCM. Copyright (C) 1996 Elsevier Science Ltd.