Simulation Analysis And Design Of Active Magnetic Bearings

The stator and rotor of a traditional motor are directly connected by mechanical bearings,so mechanical friction will occur during work.Mechanical friction will increase resistance,and the resulting loss will reduce work efficiency and wear parts.The large amount of heat brought by friction will also affect the role of lubricant,and it will also be accompanied by noise pollution.The magnetic bearing is a new type of high-performance bearing that is different from it.It uses a magnetic field to suspend the rotor so there is no mechanical contact.Therefore,it has no mechanical losses,excellent performance,high efficiency and durability.With the development of various related fields of magnetic levitation bearings,considerable progress has been made in the research design and manufacturing process of magnetic levitation bearings.This article relies on the key project "High-power high-speed motor and magnetic suspension bearing design key technology",through the electromagnetic force derivation of the active magnetic suspension bearing and determine the size parameters,as well as electromagnetic field analysis and temperature field simulation to design the active magnetic suspension bearing,specific work as follows.The paper introduces the structure,working principle and classification of magnetic levitation bearings,points out the advantages of magnetic levitation bearings,tells the development history,research status and future development trends at home and abroad,and selects active magnetic levitation bearings as the object for research.After introducing the important parts and the working mechanism of active magnetic bearings and basic theories related to magnetic bearings,the design of radial and axial bearings is mainly carried out.The electromagnetic force formula is derived from the simplified model of the radial bearing,and the number of poles is determined to be eight poles based on the relationship between the number of poles and the bearing capacity and considering the effect of magnetic coupling.The comprehensive constraints determine the dimensional parameters of the radial bearing.Based on the radial bearing,the mechanical structure of the axial bearing is deduced and the parameters are determined.On this basis,the electromagnetic field theoretical analysis was carried out on the radial bearing and the electromagnetic field simulation was compared with the finite element analysis software ANSYS Electronics.The parameter distributions were compared with the theoretical calculation results and simulation results to verify the feasibility and correctness of the above design.Finally,the thermodynamic analysis of the active magnetic bearing is carried out.Based on the heat source analysis,determine the heatsource value to be used in the simulation,and establish the fluid domain model in SolidWorks.Use the CFD software package Fluent to simulate complex flow to simulate the effect of two different sizes of input current on the active magnetic bearing to obtain the temperature.Field simulation results and analysis.Through the simulation results,it is found that the temperature of the active magnetic bearing is too high,which will adversely affect the stability of the system and the personal safety of the experimenters.Designed with the goal of reducing temperature rise,a method of installing fins with different fin counts was proposed,and temperature field simulations were conducted to obtain the results and analyze to determine the optimal parameters.An effective method to minimize the temperature rise of the active magnetic bearing during operation was obtained.Based on the theoretical analysis,this paper mainly designs the two key structures of active magnetic levitation bearings,radial bearings and axial bearings in detail.The theoretical calculation and simulation verification of the electromagnetic field of the designed active magnetic levitation bearings are carried out.Afterwards,I found the problem of high working temperature and gave a solution.There are not many domestic simulation studies on the temperature field of magnetic bearings.This paper obtained a lot of data during the design and simulation process.The results verify the effectiveness and rationality of the design and solutions,and provide some guidance for subsequent practical applications.