Optimized Design And Experimental Investigation For An Interior Permanent Magnet Synchronous Machine With Double-layer PMs For Electric Vehicles

Electric vehicles(EVs),with friendly environment and zero discharge,drawing more and more attention since the environmental pollutions and energy crisis become more serious,but there is a problem of achieving a high power density of electrical machine in electric vehicles,which restricted the development of electric-vehicle industry.Interior permanent magnet synchronous machine with double-layer permanent magnets(IPMSM-DPM)inserted into rotor,which improved the power density.This paper aim to design of IPMSM-DPM applied for the EVs,and based on the mechanism of the motor operation and the characteristics of the rotor structure,the finite element method(FEM)is used to optimize the design of the motor.The mechanical strength of the rotor under the maximum speed is verified,and the temperature field distribution of the motor parts under rated load is numerically.Finally,a prototype test was made and tested to demonstrate the effectiveness of the theoretical analysis.The research results of this paper have an important theoretical basis and engineering application value for the development of the EVs drive.The main works and achievements of this thesis are as follow:1.Optimized design of motor structure.The structure characteristics of the IPMSM is analyzed in detail.The finite element software Ansoft Maxwell is used to optimize the rotor structure.In the different stator slots,numerical calculation of the iron loss,copper loss,power factor,torque ripple and efficiency in the whole working area are carried out by Toolkit.Furthermore,some electromagnetic characteristics including the inductance,output torque,loss,and efficiency are compared to IPMSM with single-layer PMs in rotor structure.Finally,the optimization design scheme is obtained.2..Checked the rotor stress.The IPMSM-DPM rotor model is built by SolidWorks.The material properties were defined in ANSYS,and the mechanical stress distribution of the rotor under the maximum speed was calculated.The rationality of the rotor design was verified.3.Numerical calculation of magnetic-thermal coupling model.The armature winding loss and iron loss of the IPMSM-DPM at the rated load are calculated by Ansoft Maxwell.Based on ANSYS Workbench simulation platform,the three-dimensional magnetic-thermal coupling simulation model is built by using loss data as heat source,and the temperature field Distribution is achieved and deeply analyzed.4.Manufacture and experimental study of prototype.The prototype is manufactured in accordance with basic parameter and processing drawing.The testing platform is built and the basic performances are tested,including phase resistance,inductance and EMF,which verify the effectiveness of design and simulation analysis.