Design of dual stator induction motor for electric vehicular application

Abstract

With increasing concern for environmental pollution and depleting resources of crude oil, electric vehicles (EVs) are the future of automobiles. From a careful survey of existing passenger EVs, the problem identified was low torque density from existing conventional electric motors available. Hence a new type of rotary induction machine with a dual stator structure for EV and traction purposes is suggested, which is having high torque density. Designing of dual stator motor involves designing two induction motors, one with an outer rotor and the other with the inner rotor with a constraint that the inner and outer motor having an equal length as both the machines have a common dually slotted rotor. The operating characteristics of the designed machine are analyzed by an electric machine simulator, Ansys Maxwell, in open-loop operation as well as with scalar control, and also a comparative study has been done in terms of torque density and torque-speed characteristics in the whole operating range. Results show that the proposed design not only has a higher torque density but also better torque-speed characteristics in the flux weakening region of operation compared to the conventional design. Also, the designed motor has a better overall efficiency above the rated load than the conventional design.