Comparison of Magnetic Gear Characteristics Using Different Permanent Magnet Materials

In the coaxial magnetic gear, the permanent magnets of each rotor face each other, and the driving frequency of each rotor has different values according to the gear ratio. The magnetic flux that changes with time is transmitted to each permanent magnet. If the permanent magnet has conductivity property, losses by eddy currents are occurred in the permanent magnet. It is a major loss of a magnetic gear. Because the loss causes demagnetization by heat, it is mentioned a fatal problem at high speed. In this paper, the characteristics were analyzed by applying permanent magnets without conductivity. In addition, the analysis of the electromagnetic field as well as the mechanical loss were also considered to show which magnet type is advantageous.