DESIGN PROCEDURE OF 48V IN-WHEEL OUTER ROTOR SPMS FOR FULLY ELECTRIC VEHICLES

This paper proposes a design procedure of 48V in-wheel outer rotor motors for fully electric vehicles. A case study with outer-rotor surface-mounted permanent-magnet motors (SPMs) adopted in Nissan Leaf vehicle with HYZEM urban drive cycle comprehensively illustrate vehicle simulations, motor and inverter designs, cooling design and drive cycle thermal investigation. Comparison between air and liquid cooling methods is also included. In addition, different manufacturing processes of the proposed outer-rotor SPM are considered during cost modelling and a strip layout factor is defined by analytical equations to account for electrical steel scrap. Accordingly, a recommendation is given with regards to minimising waste materials during the manufacturing process.