Investigation into the Influencing Factors of the Center Magnetic Force of Anisotropic Permanent Ferrite Magnets in Motor Stator Application

Ferrite magnets employ iron oxide, a by-product of iron-making that constitutes 90% of their primary raw material. Such a sustainable material is significant for its involvement in the circular economy. Motor manufacturers can monitor for any variation in material composition or process of magnets through fluctuations in central magnetic force. Here, the simulation software JMAG is used to investigate the influence of some less-considered parameters, such as variation in height and thickness of magnets within tolerances, as well as the parameters other than the magnet, such as the change of motor housing, spring plate, and assembly position, on the central magnetic force of the anisotropic permanent magnet stator of a motor. The results reveal that the central magnetic force is positively correlated with the thickness, height, and length of the magnet, the thickness of the motor housing, and the distance between the magnet and the top surface of the motor housing, but negatively correlated with the diameter of the spring plate. This study found that, as soon as fluctuations in the center magnetic force are detected during the manufacturing process of a motor, the magnets, motor housing, and spring plates should be thoroughly examined from the point of view of the magnetic circuit system to see if there are any variations.