The torque of a magnetic gear system with different magnetic poles has
been investigated by computer-aided simulation with 2 dimensional mod
eling processes of finite element analysis. With a fixed separation of
distance, the torque shows a maximum for a special number of poles, w
hich shifts to a higher number of poles as the ratio of the radius to
the thickness of the magnets increases and shifts to a lower number of
poles with adding an iron yoke. Using this technique, we can obtain a
n optimum design of radial magnetic gear system for practical usage.