Design of a Permanent Magnet Synchronous Motor according to FreedomCAR specifications

Electric mobility is becoming in recent years a growing reality due to increase of the demand and cost of oil and the enviromental impact of conventional ICE (Internal Combustion Engine). This phenomena is becoming relevant in the western countries, that are usually large consumer but also also heavily dependent on foreign imports, especially for the transport sector: in the USA were born public-private cooperative research programs, the last called FreedomCAR, aimed at developing high efficiency and cost competitive technologies for electrification of private transport in which electric motors are the key devices. This research provide the description of the design of an high performance IPM (Interior Permanent Magnets) electric motor, according to the latest FreedomCAR 2020 targets, using an unconventional rotor with round shape polar islands; two different PMs configuration were considered, I-shape (radial magnetization) and V-shape. Both the machine are equipped with the same stator and a FSCW (Fractional Slot Concentrated Winding). The design procedure was started from a preliminary analysis, used in order to define the main characteristics of the machine while, an analytical synthesis, had led us to define the main geometry dimensions. The tuning and detailed analysis of the machines was performed using FEA (Finite Element Analysis), with particular interest to the final evaluation of losses and efficiency. The report shows the feasibility of this kind the machines, especially concerning the efficiency, that represent the most difficult constraint to achieve, and highlights also the benefits for using this unique rotor design