Calculation And Analysis Of Electromagnetic Characteristics Of Magnetic Field Modulated Two-Degree-of-Freedom Magnetic Coupler

Field modulated two-degree-of-freedom magnetic coupler,also called Linear and rotary magnetic transmission(LRMT),is a novel magnetic coupler,which is based on the principle of magnetic field modulation.In this dissertation,the equivalent subdomain model of LRMT is deeply studied,which provides a fast and effective method for initial design,characteristic study and optimization of the main structural parameters of the magnetic coupler.Firstly,the topological structure of the magnetic field modulation two-degree-of-freedom magnetic coupler is introduced,and the principle of magnetic field modulation is elaborated in detail based on the specific operation mode,and then the operation principle is analyzed.According to the given structure parameters,the two-dimensional finite element model of magnetic field modulator magnetic coupler is established to analyze the magnetic field distribution,modulation characteristics,positioning torque,positioning thrust and other static characteristics of magnetic field modulator.Secondly,an equivalent model is established and verified based on the analysis of the structural characteristics of the original model.According to the basic theory of analytic method,the equivalent model is divided into several subdomains,and the equivalent subdomain model is established based on the scalar magnetic potential.To solve the unknown constant coefficient,the boundary surface boundary conditions of each interface are analyzed and boundary equations are established.The magnetic density distribution of internal and external air gaps obtained by the equivalent subdomain model are compared with the results obtained by the Finite Element(FEM).Finally,based on the equivalent subdomain model,the torque,thrust calculation models,and the asymmetric magnetic tension calculation model of the magnetic coupler are derived,and the results calculated by the model are compared with those obtained by the FEM to verify the effectiveness of the calculation models.The influence of main structural parameters on torque and thrust are analyzed by using the relevant calculation model,and compared with the finite element simulation results further verifying the accuracy of the equivalent subdomain model.