PM-assist double stator synchronous machine

Permanent magnet synchronous machines (PMSM) have dominated several key industries such as electric propulsion of electric and hybrid electric vehicles. This is primarily due to the introduction of temperature tolerant, high energy rare earth magnets over the past two decades. The proposed magnetic configuration presented in this paper introduces an opportunity for optimal generation of electromagnetic torque. Our investigation shows that the proposed configuration can reach the power and torque densities similar to those of the interior magnet PMSM using ferrite magnets of the same volume. This will allow for removal of the need for high energy rare earth magnets, thereby allowing for sustainable production of high grade PMSM drives. The key aspect in the magnetic design of the machine deals with the tangential formation of the flux lines inside the rotor which in turn will increase the motional forces while mitigating the undesirable radial forces acting on the stators.