Study On Multi-physical Field Of Large Capacity Permanent Magnetic Coupler

Permanent magnet magnetic coupler has the advantages of good soft start and overload protection,high transfer efficiency,energy saving,environmental protection,explosion-proof,strong environmental adaptability,low installation precision,simple structure,no maintenance and so on.In this paper,the design characteristics and performance of permanent magnet magnetic coupler are studied as follows:First of all,the calculation formula of transmission torque and eddy current loss is derived by the method of magnetic circuit calculation.The Matlab software is used to program the copper disk,the size of permanent magnetic disk,the pole number of permanent magnet,and the air gap length,providing a reference for the design of permanent magnetic coupler.Secondly,the finite element analysis model of the prototype is established in Maxwell,and the distribution of magnetic density,eddy current density and air gap magnetic density are simulated when the prototype is running with rated load.Based on the finite element model,the relationship between torque,slip power,axial force and slip velocity of the prototype is studied,with the decrease of slip speed,the transfer torque increases and then decreases,the slip loss decreases and the efficiency increases gradually,the axial force is changed from gravity to repulsive force until the gravity and repulsive force are equal,the transmission torque reaches the maximum.Thirdly,based on the Ansys Workbench software,the temperature distribution of each part of the prototype is analyzed when the rated load and the maximum load are running,the results show that the maximum temperature appears on the copper disk,and the temperature of the permanent magnet material is far less than its safe working temperature,degaussing will not happen.Combined with the actual operation of the prototype,through the analysis of the stress field of checking the most prone to deformation of the permanent magnet plate,the maximum deformation is less than the prototype of the mean length of the gap,the stress changes to satisfy allowable stress criteria,a prototype can be long-term reliable operation.