Design And Analysis Of Permanent Magnet Assisted Synchronous Reluctance Motor

With the rising price of permanent magnet materials,the problem of supply and demand cannot be solved,and the advantage of ferrite is gradually highlighted.However,the low remanence of ferrite cannot meet the high torque and high power density of ordinary permanent magnet motors.In recent years,a new permanent magnet motor,ferrite-assisted synchronous reluctance motor,has been widely used in electric vehicles,compressors and water pumps.Because of the complexity of rotor structure,there is much room for improvement in the optimal design of the motor.Based on permanent magnet assisted synchronous reluctance motor complex magnetic circuit structure,the diversity of rotor structure,the motor performance of multi-objective optimization,the weak parts of the rotor stress checking,for the design of the complicated structure of motor and physical fields study provides a certain guidance and reference significance,main research contents include the following:（1）Determine the basic size of the stator of the motor based on the electromagnetic calculation formula,determine the optimal inner and outer diameters of the stator by optimizing the split ratio,compare different slot types,different winding forms,pole-slot fit and rotor structure,including different magnetic barrier shapes,magnetic barrier layers,magnetic barrier ratio,rib width and permanent magnet thickness.And the choice of silicon steel sheet material and permanent magnet material to determine the optimal performance of the motor,using finite element software to simulate the working characteristics of the permanent magnet assisted synchronous reluctance motor under different working conditions;（2）due to the complexity of the motor of the magnetic circuit structure is not mature formula of magnetic circuit,this paper improve the average torque motor,to reduce the torque ripple,the multi-objective optimization method based on the parameter sensitivity,from all design of the rotor structure size extract the structure of the key performance parameters of motor,and Latin hypercube sampling method is used to test design,The response surface of the optimized parameters is constructed,the optimal structural parameters are selected,and the reliability of the method is verified by using finite element software,which shortens the optimization time of motor design and greatly reduces the workload.（3）The rotor structure of permanent magnet assisted synchronous reluctance motor is complex and there are weak links in the rotor structure,which are located at the ribs of the rotor.Therefore,stress check is carried out on the rotor of the motor.Because the stress of rotor is seriously affected by temperature,the stress analysis under different temperature and multiple working conditions is considered.The results show that compared with the electromagnetic scheme of the preliminary design,the average torque of the motor is improved and the torque ripple is reduced.From the perspective of motor design efficiency,the motor design time is greatly shortened,the workload is reduced,and the motor meets the design index of temperature rise stress under multiple working conditions.