Research Of Surface-Mounted Permanent-Magnet Synchronous Motor Cogging Torque Based On Finite Element Analysis

Surface mounted permanent magnet synchronous motor with a small size,simple structure,high efficiency,high torque density,etc.,are widely applied to many engineering fields,it is very potential energy saving motors.Although the permanent magnet motor has many advantages,but still there are some problems affecting its output performance worthy of study and discussion,the more important one is the cogging torque.This permanent magnet motor cogging own existence will lead to the physical structure of the motor produces a torque,even in the case where the armature windings are not energized by this still will have a similar torque,the cogging torque.Cogging torque of the motor will produce torque ripple,causing vibration and noise,the motor is difficult to run smoothly,affect the overall performance of the motor.In addition,the cogging torque and position control system will also speed control system accuracy and performance produced significant effect.Therefore,this study cogging torque of great significance to improve the performance of the motor.The main work focused on the following areas:Firstly,the mathematical model of permanent magnet synchronous motor is established,and its steady-state performance and magnetic circuit design are deeply studied,which is the basis for the design of permanent magnet synchronous motor.Then it analyzes the mechanism of cogging torque is produced and its calculation method.Focusing on the influence of semi-circular auxiliary slot on the permanent magnet synchronous motor cogging torque.The semicircular groove structure of auxiliary motor stator is improved,using the motor design software MotorSolve for finite element analysis of the motor model,obtained the cogging torque with auxiliary slot radius,groove number,slot position and other parameters,and effect of auxiliary slotparameters on electromagnetic torque,the motor back EMF and no-load air the gap magnetic flux density waveform was studied.Study on method of weakening cogging torque based on the auxiliary tank,this paper describes the design of a permanent magnet synchronous motor,and the auxiliary tank is applied to the design of the motor.In order to design a high performance permanent magnet synchronous motor,the stator slot,wire winding of motor,permanent magnet and air gap parameters were optimized,and the motor cogging torque,temperature field,loss,air gap flux density and other properties of the finite element analysis,the final design the mechanical structure of the motor.Experimental analysis of the prototype processed,the experimental results are basically consistent with the simulation results show that the auxiliary tank can reduce the cogging torque of the motor,torque ripple suppression.