Conference: 한국자기학회 동계학술연구발표회
Authors: Kyoung-Soo Cha, Young-Hoon Jung, Chung-Seong Lee, Myung-Seop Lim
DOI:
Due to environmental regulations, the eco-friendly vehicle industry is growing noticeably. The eco-friendly vehicles include hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV), battery electric vehicle (BEV), and fuel cell electric vehicle (FCEV). Recently, various studies on EVs have been conducted. The majority of research on EV traction motors aims at improving efficiency and increasing power density. Improving motor efficiency and power density can improve mileage because it reduces energy consumption. The most suitable motor that meets these requirements is interior permanent magnet synchronous motor (IPMSM) using Neodymium (Nd) magnets. Therefore, many studies on IPMSM are performed. However, Nd magnets, which are rare earth magnets, have disadvantages of price instability. Therefore, in order to replace IPMSM, the researchers discuss various non-rare-earth motors.
Wound field synchronous motor (WFSM) and concentrated flux synchronous motor (CFSM) are representative non-rare earth motors. However, WFSM has a low power density. Also, it is not suitable as a traction motor because of the brush and slip ring. CFSM is suitable as a traction motor because it can have a power density similar to that of IPMSM. CFSM is spoke type motor using non-rare earth magnet. Ferrite magnets, which are non-rare earth magnets, have a residual magnetic flux density of about 30% compared to Nd magnets. Therefore, in order to increase air-gap flux density, magnets are arranged in the shape of the spoke.
In this paper, CFSM is designed to have the same power density as IPMSM. These motors are designed for EV traction. As a result of 2-dimensional finite element analysis, the performance of IPMSM and CFSM is compared. Finally, vehicle simulations are used to compare system efficiencies for vehicles using CFSM and IPMSM as traction motors. For vehicle simulation, the target driving cycle is urban dynamometer driving schedule (UDDS).