This paper conducted a study on the reduction of the number of split Magnetization and the prevention of irreversible demagnetization using the I-Core of a double spoke type motor. Recently, as interest in spoke-type motors using ferrite permanent magnets has increased, the need for research on magnetization and irreversible demagnetization in double spoke-type rotor shapes has emerged. However, in the existing spoke-type rotor shape, the magnet was deeply embedded in the rotor, making it difficult to magnetization. As it is important to use permanent magnets excluding rare earths in the future, the use of spoke-type motors becomes important, and design to consider magnetization and prevent irreversible demagnetization accordingly is important. Therefore, this paper proposed a magnetization yoke shape design in consideration of magnetization and irreversible demagnetization on using I-Core of Double Spoke type PMSM to solve this problem.
Currently, the price of rare earth materials is soaring to the highest level due to the rapid increase in demand for rare earth materials worldwide. Against this background, permanent magnet motors (PMSM) using existing rare earths are increasing in manufacturing costs and the electric motor used to solve this problem is a spoke type permanent magnet synchronous motor (PMSM) using a ferrite permanent magnet. However, the general spoke type PMSM does not have much difference in inductance between the d-axis and the q-axis, so the use of the reluctance torque is small. However, this shape is a conventional magnetization model, and there is a disadvantage that it does not become a magnet when magnetization proceeds. Since there is an increase in the number of magnetization and inconvenience in a irreversible demagnetization during division and magnetization, a magnetization yoke shape is proposed to solve this problem. This study investigated the method for reducing the number of magnetization in the existing split magnetization method using I-Core of Double spoke type PMSM and the magnetization yoke shape to prevent irreversible demagnetization.
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Fig. 1 It is a rotor shape using I-Core.

Fig. 2 It is the magnetization result of a double spoke type rotor.