Magnet-based vs. magnet-free electrical machines for low power automotive applications

In his paper he authors present a comparison between magnet-based and magnet-free motors for an oil pump used in automotive applications. From the first category, two inset permanent magnet (IPMs) synchronous motors are chosen whereas the later group of motors is represented by a double stator switched reluctance machine (DS-SRM). The three-phase 12s/8p and 12s/10p IPMs are compared with the four-phase 16/12 DS-SRM in terms of torque capability, power density, efficiency and cost of active materials. Comparisons were conduced both at room and high temperature and assuming two different values for the DC-bus voltage: 12V and 48V. Some rather general remarks are done about the noise vibration and harshness problems (NVH) ha an electrical machine for automotive applications designer has to deal with.