12 Slot — 10 Pole excited synchronous motor design for ISG applications

Since a belt driven integrated starter and generator (ISG) can make a vehicle hybridized with a minor modification, it receives a great attention recently. It provides vehicles “stop and go” function, as well as power generation like an alternator. A 12 slot - 10 pole excited synchronous machine (ESM) is designed and analyzed via JMAG in this work. The ISG is required to have a high starting torque (43 Nm) and a high speed range (~18000 rpm). Apart from Nd-free advantage, a ESM has a freedom of controlling the field current: Thereby it is not necessary to apply a high negative d-axis current at a high speed, reducing thermal load. In this design, an optimum split ratio is investigated over copper and iron losses. It is also found a proper field current capable of producing a rated power satisfying the voltage limit at a maximum speed.