Optimal rotor structures to reduce Windage Loss and their impact on Acoustic Noise and Vibration in Switched Reluctance Motors: Application to L5M and L5N electric-three wheelers

Two Switched Reluctance Motors (SRMs) rated to 3 kW and 6 kW have been designed for L5M and L5N (High-speed passenger and cargo) electric three-wheeler traction application. As the traction application requires the SRMs to operate in a wide operating speed range up to 12000 rpm, windage loss and acoustic noise becomes a problem of concern. To reduce the windage loss, the slot shape of the rotor is changed to minimize the slot area while meeting the torque developed by the motor. To understand the impact of change in the rotor slot on noise and vibration, a detailed noise simulation study is performed. To validate the simulation results, prototyping of the optimal rotor structure followed by experimental tests are carried out and the results are compared.