Research On Permanent Magnet Synchronous Motor With Double V-shaped Rotor Magnet Structure And Its Drive System For Electric Vehicle

With increasing attention to environmental issues,the research and application of electric vehicles have received extensive attention.The motor and its controller are the core components of the electric vehicle power system,so improving the performance of the motor and its driver is of great significance to the development of electric vehicles.In order to improve the driving performance of electric vehicles,this paper studies the dual V-rotor magnet structure permanent magnet synchronous motor and its related drive system,which has theoretical and practical value.The main research content of this paper is as follows.(1)The significance and current research status of the subject are described,including the current research status of electric vehicle motors,magnetic network method and motor stator winding switching.(2)The permanent magnet synchronous motor double V rotor magnet structure and motor stator winding switching operation are studied.First,a permanent magnet synchronous motor with a double V-shaped rotor magnet structure and a rated power of 150kW was designed,and the electromagnetic field finite element method was used to study it;Then,according to the structure of the motor,a driving method of the switching operation of the stator windings is proposed,and compared with the field weakening control,the advantages of the switching operation of the permanent magnet synchronous motor stator windings are analyzed;Finally,Simulink is used to analyze the switching operation of the permanent magnet synchronous motor winding,and the parameter changes during the winding switching process are studied.(3)A dynamic magnetic network model of the permanent magnet synchronous motor with a double V-shaped rotor magnet structure is established.Based on this dynamic magnetic network model,the performance of the motor is analyzed and calculated,and the calculation results are compared with the electromagnetic field finite element method and test results.First,a dynamic magnetic network model of the permanent magnet synchronous motor with a double V rotor magnet structure is established;Then the nonlinear equations of the model are established based on the nodal magnetic potential method,and the nonlinear equations are solved by the chord cut method and the motor performance is calculated;Finally,the calculation results of the permanent magnet synchronous motor with double V-shaped rotor magnet structure based on the dynamic magnetic network method are compared with the calculation results of the finite element method and the experimental results.(4)A vector control joint simulation model of the permanent magnet synchronous motor with a double V rotor magnet structure based on the dynamic magnetic network model and the motor stator winding switching operation is established,and the established model is used for dynamic simulation.First,the principle of joint simulation of dynamic magnetic network model and vector control model based on motor stator winding switching operation are introduced;Secondly,use the dynamic magnetic network model to calculate the permanent magnet flux linkage,direct axis and quadrature axis synchronous inductance when the stator windings of the motor are connected in different ways,and organize the calculated motor parameters into a motor dynamic parameter database to provide parameters for the vector control model;Finally,a variable parameter vector control model based on the motor stator winding switching operation is established.In the process of model simulation,the permanent magnet flux,phase resistance,direct axis and quadrature axis synchronous inductance of the motor are modified in real time according to the parameter database and speed of the motor to complete the stator winding switching,and the three-phase current,speed and other waveforms of the motor at different speeds and loads are calculated according to the model(5)Manufacture prototypes,build motor experiment platforms,and conduct experimental analysis on prototypes.First,manufacture the prototype according to the prototype design parameters,and build the motor experiment platform;Then the no-load back-EMF waveforms of the prototype at different speeds and stator winding connections are measured,and compared with the calculation results of the dynamic magnetic network model,which verified the accuracy of the dynamic magnetic network model established in this article;Finally,the motor experiment platform is used to drive the prototype,and the stator current waveforms of the prototype running in different gears are measured.