Dynamic performances of a magnetic thrust bearing based on new soft magnetic composites

摘要

According to the material theory and analysis method, the characteristics of the soft magnetic composites were analyzed. As the required magnetic properties can be achieved by adjusting the formulation ratio, the high electrical resistivity (about 10(-4) omega m) and decent magnetic properties were obtained. Based on the good performance, soft magnetic composites were firstly applied to the magnetic thrust bearings. The dynamic models including the dynamic stiffnesses, magnetic force based on the effective reluctance model were analyzed. The parameters for soft magnetic composites were obtained by experiments and theoretical calculations. The results showed that the dynamic bandwidth of magnetic force for the bearing with MgO-based soft magnetic composites can reach more than 1000 Hz, which is far beyond that for carbon steel bearing. If the magnetic permeability is further increased to 650, the dynamic bandwidth of the electromagnetic force can also exceed 1000 Hz for the magnetic thrust bearings made by soft magnetic composites. Therefore, the possibility of magnetic thrust bearing made by soft magnetic composites instead of carbon steel materials is equipped with the satisfactory performance, which may provide a theoretical basis and technical support for high-performance magnetic thrust bearing.