Temperature rise anomaly analysis of the stator winding in large-capacity high-torque-density evaporate cooling induction motor

Compared to traditional air cooling, evaporative cooling has the advantages of better cooling performance, lower noise, and low power consumption. An induction motor using evaporative cooling technology can achieve high efficiency, high torque density, and low noise. But during the temperature rise test, an anomaly was detected that the local temperature rise in the motor stator winding was too high. To investigate this problem, simulation analysis and experimental tests have been performed. The slot gap between the stator windings and the core as well as the axial tooth coolant duct are identified as root causes for the temperature rise anomaly. Then, the influence of the stator winding's temperature was analyzed to include the slot gap. This research will serve as a useful technical reference for application of evaporative cooling technique to induction motors.