Improvement of Traction Motor Performance for Electric Vehicles Using Conductors With Insulation of High Thermal Conductivity Considering Cooling Methods

• Published in: IEEE transactions on magnetics 2021-02, Vol.57 (2), p.1-5
• Main Authors: Huynh, Thanh Anh, Hsieh, Min-Fu
• Format: Article
• Language: English
• Subjects: Coils (windings); Conductors; Cooling; Cooling rate; Electric vehicle (EV); Electric vehicles; Flow velocity; Heat conductivity; Heat transfer; Induction motors; Insulation; interior permanent-magnet synchronous motor (IPMSM); Liquid cooling; Magnetism; Permanent magnet motors; Permanent magnets; Thermal conductivity; thermal conductivity (ThC); Traction; traction motor; Traction motors; winding temperature; Windings
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2020.3021127

This article utilizes conductors with insulation of high thermal conductivity (ThC) combining suitable cooling methods to enhance the performance of traction motors for electric vehicles. The performance of a 10 kW interior permanent magnet (IPM) motor without forced cooling is considered as a benchmark. Then, the conductors with two conventional insulation materials and two with high ThC are applied to the IPM motor windings. Two cooling methods, finned housing (no forced cooling) and water cooling, are considered here. It is found that using conductors with high ThC insulation without forced cooling can only cool the windings by several degrees; however, the temperature can be considerably reduced by combining water cooling with an appropriate flow rate. The torque and power output of the IPM motor can also be significantly improved. This indicates that forced cooling can further enhance the effectiveness of conductors with insulation of high ThC. Two induction motors using conductors with two different insulation materials (0.1 and 3 W/ \text{m}\cdot \text{K} ) are tested. The experimental results validate the analysis.