Magnetic-thermal Coupling Analysis And Multi-objective Optimization Of Amorphous Alloy Permanent Magnet Synchronous Motor

In the past ten years,China has continuously vigorously promoted the development and progress of electric vehicles,aerospace power generation and other fields.In these important fields,permanent magnet synchronous motors stand out by virtue of their high efficiency,high power density,small size,light weight and other characteristics.However,the working environment of permanent magnet synchronous motor is relatively complex,which is easy to cause high temperature rise and then overheat the motor.Once the motor overheats,the insulating material between the silicon steel sheet and the stator winding will be damaged,and the permanent demagnetization of the permanent magnet will lose its function,which will greatly interfere with the normal operation of the permanent magnet synchronous motor.Based on the above reasons,we should properly optimize the structure of permanent magnet synchronous motor and reduce its temperature during operation.Because the loss of amorphous alloy is much smaller than that of silicon steel sheet,and iron loss has a high proportion in permanent magnet synchronous motor.Therefore,in this thesis,amorphous alloy is used as the stator core material of permanent magnet synchronous motor.The electromagnetic characteristics of amorphous alloy permanent magnet synchronous motor and silicon steel permanent magnet synchronous motor as well as the temperature distribution of motor components during operation are deeply studied and compared,and the structural multi-objective optimization of amorphous alloy permanent magnet synchronous motor is carried out.First of all,this thesis analyzes the working principle and mathematical model of permanent magnet synchronous motor,and proposes a new type of permanent magnet synchronous motor(IPMSMB)based on the common permanent magnet synchronous motor(IPMSM).The 2D motor model of IPMSMB is established by using Ansys Maxwell,and then the electromagnetic performance of IPMSMB and IPMSM under no-load and load conditions is simulated and compared.Secondly,the amorphous alloy 1K101 is used to replace the ordinary silicon steel sheet of IPMSMB stator material,and the temperature field simulation analysis is carried out for two different stator materials of the motor.The results show that the overall temperature of the amorphous alloy motor is lower than the overall temperature of the silicon steel motor.At the same time,the electromagnetic properties of amorphous alloy motor and silicon steel motor are compared and analyzed.The results show that the electromagnetic properties of amorphous alloy motor are better than that of silicon steel motor.Thirdly,in order to improve the electromagnetic performance of the amorphous alloy motor,this thesis selects the output torque,torque ripple and cogging torque of the motor as the optimization objectives,uses Taguchi method to carry out multi-objective optimization of the structure of the amorphous alloy motor,and compares the electromagnetic performance of the motor before and after optimization.The results show that the electromagnetic performance of the amorphous alloy motor after optimization has been improved to a certain extent.At the same time,the temperature field of the amorphous alloy motor after structure optimization is analyzed,and the results show that the overall temperature difference of the motor before and after structure optimization is small.Through sufficient theoretical analysis and finite element simulation research on the magneto-thermal coupling analysis and multi-objective optimization design of the amorphous alloy permanent magnet synchronous motor,the validity and correctness of the new structure and its analysis method are verified.The research conclusions of the thesis provide valuable reference for the wide application of this type of motor.