Comparison of Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass Conference Paper uri icon


  • 2017 IEEE. This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a stall torque of 500 Nm and a gear ratio of approximately 5, to independently maximize volumetric torque density (VTD), torque per dollar (TPD), and gravimetric torque density (GTD). Maximum VTDs of 274 kNm/m3 and 210 kNm/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 Nm/ and 5.47 Nm/ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 Nm/kg and 86.8 Nm/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different optimal design selections.

name of conference

  • 2017 IEEE International Electric Machines and Drives Conference (IEMDC)

published proceedings


author list (cited authors)

  • Gardner, M. C., Jack, B. E., Johnson, M., & Toliyat, H. A.

citation count

  • 8

complete list of authors

  • Gardner, Matthew C||Jack, Benjamin E||Johnson, Matthew||Toliyat, Hamid A

publication date

  • January 2017