Abstract
We designed and analyzed an interior permanent magnet synchronous motor (IPMSM) to prevent irreversible demagnetization of the permanent magnets (PMs). Irreversible demagnetization of NdFeB PMs mainly occurs due to high temperature, which should thus be minimized. Therefore, it is necessary to reduce the eddy current loss in the PM through optimal design. The shape of the rotor core was optimized using finite element analysis (FEA) and response surface methodology. Three-dimensional (3-D) FEA is required for accurate computation of the eddy current loss, but there is huge time, effort, and cost consumption. Therefore, a method is proposed for indirectly calculating the eddy current loss of PMs using 2-D FEA. A thermal equivalent circuit analysis was used to calculate the PM temperature of the optimized model. For the thermal analysis, the copper loss, core loss, and eddy current loss in PMs were estimated and applied as a heat source. Based on the results, we confirmed the stability of the optimum model in terms of the PM demagnetization.
Highlights
Interior permanent magnet synchronous motors (IPMSMs) using Nd-Fe-B magnets have been developed for traction motors in electric vehicles (EVs) and hybrid electric vehicles (HEVs)
We calculated them by finite element analysis (FEA), composed of the copper loss, core loss, and PM’s eddy current loss
This study presented design processes to prevent irreversible demagnetization by reducing eddy current losses in a PM
Summary
Interior permanent magnet synchronous motors (IPMSMs) using Nd-Fe-B magnets have been developed for traction motors in electric vehicles (EVs) and hybrid electric vehicles (HEVs). The PM is inserted into the rotor core in a solid form, so shape optimization is needed for the minimization of the heat generation of the PM due the return path and the axial direction of the eddy current cannot be ignored. Optimalmodels design in was performed to reduce the eddy current an of indirect a PM in method this study, and the the analyze various the optimization process, we propose to estimate temperature inside the PM was predicted through thermal equivalent circuit analysis [22]. A thermal equivalent circuit analysis was conducted optimization was performed to reduce the eddy current loss in the PM using 2-D FEA based on an with consideration of the eddy current loss in the PMequivalent calculatedcircuit by 3-D.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
