| Based on the magnetic field modulation effect,this paper presents a novel magnetic gear with intersecting axes(MGIA).Which not only has all the advantages of the traditional magnetic bevel gears,like no contact,lubrication-free operation and in-built overload protection,ect,but also provides high permanent magnet utilization and high output torque.Because of a straight ferromagnetic pole-pieceses,the mechanism has a small volume,which makes the mechanism have a high torque density.Based on the mechanism of magnetic field modulation and the topology structure of the MGIA,the constraint relationship of the design parameters was deduced.The 3D parametric finite element model of the mechanism was established using the electromagnetic simulation software Ansys Maxwell,and the vector distribution of the magnetic flux density of the mechanism was analyzed.The harmonics of the radial and tangential magnetic flux densities in the middle of each air gap,as well as the static torques and harmonics of the input and output rotor were calculated.It was concluded that the main harmonics of the air gap magnetic field at the input and output sides,the main harmonics of the torques on input and output rotor were all respectively equal to the numbers of pole-pairs of permanent magnets on the input and output rotors,which revealed the drive mechanism of the mechanism.By the electromagic simulation software,Ansys Maxwell,the Influence of the main design parameters on the output torque and the torque density were obtained,the design range of the main parameters were worked out.Based on the optimization software Isight,the response surface approximate model between the MGIA’s main design parameters and the optimization objective was established.The NSGA-II was used to optimize the approximate model and the optimal structural parameters of the MGIA were obtained.The structural design,production and debugging of the MGIA were completed,the static torque test platform of the prototype was built.By comparing with the finite element simulation results,verify the correctness of the simulation calculation and the rationality ofthe prototype design.Based on the topological structure of the MGIA,two kinds of field modulated magnetic gear with parallel axes and two kinds of field modulated magnetic gear with crossed axes were proposed,and their topological structure were introduced. |
