Analytical method for optimal design of synchronous reluctance motor for electric scooter application

Document Type : Article


Department of Electrical Engineering, Shahid Beheshti University, Tehran, Iran


In recent years, synchronous reluctance motor (SynRM) has attracted the attention of researchers and well-known companies have been involved in designing and manufacturing electric motors due to its simplicity (no need for a rotor cage and permanent magnet), the similarity of its production line analogous to that of the induction motor, low production cost and also, compared to the induction motor, better performance, if optimally designed. Saliency ratio, defined as the ratio of the d axis inductance to the q axis inductance, is the most important parameter in designing a synchronous reluctance motor which has a major impact on achieving both maximum power factor and maximum torque. The current study aimed to provide a comprehensive approach to design a series of synchronous reluctance motors using both combined methods and finite element analysis to achieve an algorithm which is based on the similarity between flux lines and the shape of flux barriers to achieve both maximum torque and minimum torque ripple. The designed motor is intended to be used in an electric scooter application. Therefore, the geometrical dimensions of the motor, such as the motor stack outer diameter and length, are held constant in all cases.


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