Rotor Design And Performance Analysis Of The Thin Ring Axial-flux Motor

With the development of rare earth permanent magnet materials,the magnetic properties of permanent magnets have been greatly improved,and permanent magnet motors are more and more widely used in industrial and agricultural production and daily life.In the low-speed application field,the traditional permanent magnet motor has more pole logarithms and more complex structures.Under this background,the permanent magnet vernier motor with the characteristics of low speed and high torque has been developed rapidly and attracted more and more attention.Based on a permanent magnet vernier motor applied to the focusing system,the finite element analysis model was established and the output performance of the motor were compared under different core materials and structural parameters,so as to further reduce the cost and improve the output performance of the motor.Soft magnetic composite material is a new kind of magnetic material with excellent performance.It has the characteristics of easy processing,isotropy and small eddy current loss,and it has been widely used in electric motors.In this paper,the finite element analysis method is used to study and compare the performance of the motor when the traditional silicon steel sheet material and the soft magnetic composite material are used as the core,and the prototype of the motor with the soft magnetic composite material as the core is made.In the application of focusing system,it is necessary to reduce torque ripple as much as possible to ensure the focusing accuracy.The cogging torque is one of the main sources of torque ripple of permanent magnet motor.The main factors affecting cogging torque are analyzed and studied through theoretical derivation.Based on the theoretical analysis results,the pole arc coefficient and shape of the permanent magnet were improved,and the tooth torque was effectively reduced under the premise of ensuring the output torque of the motor,which was verified by the finite element analysis.Halbach array is a special arrangement of permanent magnets,which can weaken the magnetic field on one side and strengthen the magnetic field on the other side.Therefore,it is widely used in the surface-type permanent magnet motors.In this paper,the application effect of Halbach array under the lifting motor model is studied and compared with the traditional model.Based on the analysis of the characteristics of the magnetic circuit of Halbach array,an improved structure based on the traditional permanent magnet arrangement is proposed,and the superiority of the proposed magnetic circuit structure over the traditional structure is verified by the finite element analysis.By combining the soft magnetic composite material with the new magnetic circuit structure,the motor model which meets the requirement of performance parameters is obtained.Finally,the performance parameters of several models are compared comprehensively,and the advantages and disadvantages of each model are analyzed.The test platform of the motor was built,the prototype of the silicon steel sheet material and the prototype of the soft magnetic composite material were tested.Based on the main performance parameters,the feasibility of the application of the soft magnetic composite material in the motor model was verified by comparative analysis.