Research On Speed Regulation Of Outer-rotor Switched Reluctance Motor Based On New Driving Topology

In recent years,under the double effects of policy and market,the new energy electric vehicle industry has made considerable and effective development,which will help alleviate the current energy shortage and environmental pollution problems,and help our country to realize the "double carbon" goal soon.The hub motor electric vehicle eliminates the transmission parts,integrates the driving motor and reducer components into the wheel,simplifies the vehicle structure,reduces the mechanical loss,and is widely regarded as the final driving form of the future development of electric vehicles.Outer-rotor Switched Reluctance Motor(OSRM)has simple structure,independent phases,stable and reliable,can work in harsh environment for a long time,and is very suitable for electric vehicle hub motor.In view of the disadvantages of the traditional asymmetric half-bridge power converter,which makes the motor system large in volume,increase in cost and decrease in system reliability when driving polyphase OSRM,this paper proposes a new power converter,fivephase full-bridge IGBT power converter,and analyzes its working principle and control method.The two-dimensional static magnetic field of the five-phase 20/16 pole OSRM prototype model was calculated by using finite element software,and the magnetic field lines and flux density distribution of the motor at four special angles were analyzed.A Switched Reluctance Drive(SRD)system containing a prototype nonlinear dynamic model was built in Matlab/Simulink using the obtained flux and magnetic common-energy characteristic curves.Experiments on no-load speed control,on-load speed control and braking were carried out based on the five-phase full-bridge IGBT power converter and the asymmetric half-bridge power converter,respectively.The simulation results verify the feasibility and superiority of the proposed power converter.The hardware and software design of the motor system is completed,and an OSRM prototype speed regulation experiment platform based on five-phase full-bridge IGBT power converter is established.The main hardware includes processor,power device and its driver,clamp protection and isolation circuit,a variety of sensor wiring circuit,etc.The program flow chart of the control system is described,including the main program,precharge control subroutine,ADC sampling interrupt subroutine,etc.Experiments on noload speed regulation,on-load speed regulation,anti-disturbance and braking of the prototype are completed.The experimental results verify the feasibility of the prototype drive system,the rationality of the control logic of the new power converter switch tube and the correctness of the simulation results.The innovation point of this project is to put forward a new type of power converter which can reduce the volume and cost of the motor system.And through a series of simulation and real experiments,the feasibility of the proposed scheme is verified.The SRD composed of this new type of power converter has a good speed control effect on the OSRM prototype.