Temperature control of permanent-magnet synchronous motor using phase change material

This paper presents a design of a permanent-magnet synchronous motor (PMSM) casing with organic phase change material (PCM), paraffin, stuffing to absorb and store the heat produced by the motor so as to prevent the motor temperature from sharp increase or decrease, and more important to avoid the motor from overheating. The paraffin is filled in the hollow motor casing on which some cavities are made specially and no complicated water-cooling or fan units are needed for the motor cooling. Mathematical models are established. Temperature variation curves of motor casings with different structure parameters and different types of paraffin are simulated on several motor operating duty cycles to observe the temperature control effectiveness of this method. Results demonstrate that the temperature of the casing could be controlled around a certain value depending on the melting temperature of the sufficient paraffin filled in the casing whose re-solidification time should be long enough in every operating period of the motor. Thus, the temperature-rise of the PMSM with paraffin casing can be controlled into a smaller range (around 55K if the melting temperature of the paraffin is 353.15K with the initial value of 298.15K) compared with that of the same size casing without paraffin (ranged from 41.491K to 71.346K). At the same time, the continuous operating time of the PMSM can be extended much longer with a PCM filled casing.