Design And Performance Study Of Laminated Axial Redundant Magnetic Bearing

The high reliability magnetic bearing system has been paid more and more attention since the deepening of the research of magnetic bearing technology and the continuous expansion of the field of application.Redundancy design is an effective way to improve system reliability.On the other hand,for active magnetic bearings,the temperature rise during operation can significantly affect the reliability of the active magnetic bearings.In this paper,a laminated axial redundancy magnetic suspension bearing(abbreviated as a laminated magnetic bearing)structure is proposed based on the requirements of high reliability of magnetic bearing.Laminated magnetic bearing has redundant features and reduced eddy current loss and temperature rise,it has obvious advantages comparing with the integral axial magnetic bearings.First of all,theoretical research is carried out in three steps.For the rigor of the study,the paper will compare the performance of the laminated magnetic bearing with the performance-optimized monolithic axial-magnetic-levitation bearings.The first step,the structure optimization of the integral axial magnetic suspension bearing is carried out by Matlab,make the bearing capacity maximum under the condition of a certain volume.In the second step,four kinds of laminated magnetic bearing structures are proposed and determined structural parameters.The third step,using Matlab,Ansys workbench and other tools on the simulation of proposed laminated magnetic bearing.And four kinds of laminated magnetic bearing are compared with the integral axial magnetic suspension bearings in terms of redundancy,mechanical characteristics and temperature characteristics.Then,test verification study.The experimental verification is also carried out in three steps,respectively verifying the redundancy,mechanical and temperature characteristics of the proposed laminated magnetic bearing.Select eight laminated magnetic bearings for verification experiment.In the first step,the eight laminated magnetic bearings can be stably suspended verifies the correctness of load-bearing capacity calculation.In the second step,under eight laminated magnetic bearings are suspended in steady state,any group of coil failures can still work normally by feedback control system.It is verified that eight laminated magnetic bearings has redundancy characteristics.In the third step,the infrared thermal imager is used to test the temperature field of the laminated magnetic bearing under regular working condition.The feasibility and accuracy of the temperature field simulation is verified by comparing the experimental results with the simulation results.Finally,according to the simulation and experimental results,it can be known that The stator part adopts a laminated magnetic bearing with magnetic material nested in laminated structure of silicon steel has the redundancy characteristic with respect to the integral axial magnetic suspension bearing without decreasing the bearing capacity,Lower temperature rise.Compared with the integral axial magnetic bearing,The stator part adopts a laminated magnetic bearing with non-magnetic material nested in laminated structure of silicon steel has the redundancy characteristic and can reduce the temperature rise to a large extent,though the bearing capacity is decreased.