Lumped-Parameter Thermal Model of Induction Motor under Phase Open-Circuit Fault

Abstract

The estimation of induction motor temperature at rated load under normal and faulty conditions is investigated in this paper. Motor temperature is estimated using thermal models based on the lumped parameters and distributed losses. The thermal model accounts the heating sources, cooling sources and the thermal resistances in the motor. The proposed model is used to study motor behaviour during balanced condition and during opening phase situation. Motor temperature during these states is predicted by the validation of the global thermal network model. It is shown that under faulty condition motor temperature rise exceeds widely the normal operating temperature. The curves of the temperature rise at different motor elements are presented.