| Title |
Comparison of pole-slot combinations of IPMSM/SPMSM for miniaturization of permanent magnet synchronous motors for electric vehicle water pumps |
| Authors |
박수진(Su-Jin Park) ; 이현태(Hyun-Tae Lee) ; 최윤진(Yun-Jin Choi) ; 한재영(Jaeyoung Han) ; 박현종(Hyun-Jong Park) |
| DOI |
https://doi.org/10.5370/KIEE.2026.75.5.1217 |
| Keywords |
Electric Vehicle; Water Pump Motor; IPMSM; SPMSM; Pole-Slot Combination; Finite Element Analysis |
| Abstract |
This paper presents a comparative analysis of interior permanent magnet synchronous motors (IPMSM) and surface permanent magnet synchronous motors (SPMSM) with different pole-slot combinations for downsizing electric vehicle (EV) water pump motors. In electric vehicle thermal management systems, water pump motors are required to deliver sufficient flow rate and pressure within limited installation space, necessitating compact and efficient motor designs. Three compact motor models were designed by reducing the stator outer diameter from 70 mm to 58 mm, and the winding turns of each model were adjusted to satisfy identical rated output and permanent magnet usage conditions. The electromagnetic performances of SPMSM and IPMSM models were analyzed under these conditions. Two-dimensional finite element analysis was employed to evaluate torque characteristics, cogging torque, back-electromotive force, and magnetic flux density distributions. The analysis results show that the SPMSM structure exhibits increased cogging torque and torque ripple due to the reduction in pole arc angle to satisfy the identical magnet cross-sectional area condition. The IPMSM with an 8-pole 12-slot configuration provides the lowest back-EMF, ensuring sufficient voltage margin, but exhibits relatively high torque ripple due to the reduced rotor outer diameter. In contrast, the IPMSM with a 4-pole 6-slot configuration exhibits the lowest torque ripple and cogging torque among the compared models, while also showing balanced characteristics in terms of back-EMF and efficiency. The results demonstrate that the IPMSM with a 4-pole 6-slot configuration is the most suitable pole-slot combination for the compact design of EV water pump motors. |