Parameter optimization and design improvement for experimental prototype of coaxial magnetic gear

For problem of low torque density existing in experimental prototype of coaxial magnetic gear with gear ratio of-15/7, 2D finite element method(FEM) are used to analyze influence of ferromagnetic pole-pieces(radial teeth height, relative teeth width and mechanical bridges connecting the modulator segments) and magnetization manners and volumeon torque density, to find improvement measures. The results show that the torque density can be increased by 43% and the outer diameter of coaxial magnetic gear can be decreased by 7.5mm due to the improved parameters of ferromagnetic pole-pieces and permanent magnet without increasing manufacturing costs.