Dynamic Analysis of Vertical Magnetic Suspension System Rotor Dropping to Protective Bearing with Different Structural Parameters

Aiming at the problem that the rotor of vertical magnetic suspension system falls to the protective bearing with different structural parameters and causes its failure, in this paper, the dynamic model of the inner structure of the protective bearing, the mathematical model of axial and radial collision between the rotor, the inner ring of the protective bearing are established. The author changed the two structural parameters of protective bearing with and without cage and the ball filling number, and the impact characteristics of WNCPB (with no cage protective bearing) and WCPB (with cage protective bearing) on the rotor were compared and analyzed. Finally, the protective bearing performance testing machine of the magnetic bearing system was built to simulate and calculate the impact force of the outer ring, and the indirect measurement experiment of the axial and radial impact force of the protective bearing with different structural parameters was carried out. The empirical results show that: the impact resistance of WCPB improved with the ball filling number increasing from 26 to 28. The number of WNCPB filled balls should be slightly less than the number of full balls to obtain optimal impact resistance. With the ball filling number increasing from 26 to 28 and then to 30, WNCPB with the ball filling number 28 has the best impact resistance. Compared to WNCPB, the overall performance of WCPB is improved.