Simulation Design And Experimental Research On Direct-drive Wheel-side Motors Of Electric Vehicles

At present,distributed driven electric vehicles generally use hub motors instead of internal combustion engine driven vehicles.Hub motors are large in size and heavy in weight,which increases the unsprung weight of the vehicle and reduces the handling performance and comfort of the vehicle.In addition,the hub motor is difficult to dissipate heat,and is prone to failure in the harsh form environment,with low reliability.The wheel-edge motor has the advantages of light weight,small volume and good heat dissipation effect,so it is very suitable for distributed driving vehicles.In this paper,the design is a direct-drive wheel-edge motor,which saves the reducer and further reduces the unsprung weight.In this paper,a 5KW direct-drive wheel-side motor is designed according to the parameters of a certain vehicle model.The main research contents are as follows:According to the parameters of the target vehicle,the power requirements under three working conditions are calculated respectively,and the rated power,rated speed and rated torque of the wheel side motor are obtained.Using the 2D module of ANSOFT Maxwell,the designed electromagnetic scheme was parameterized and analyzed.The counter electromotive force(EMF),flux linkage,cogging torque and output torque of the wheel-rim motor with different parameters were compared with slot width,permanent magnet thickness and air gap size.According to the results of parametric analysis,the appropriate parameter size is selected to improve the motor design.For the improved motor wheel and electromagnetic field analysis,studied the wheel motor under no-load conditions of static and transient field,and studied the load conditions of static and transient field,the study found that the improved wheel motor magnetic field distribution uniformity,flux density distribution is periodic,counter electromotive force and the flux distribution is sine,output torque meet the design requirements.Solidworks(SW)is used to establish the overall three-dimensional model of the wheel-edge motor,and the spindle,cooling structure and braking structure of the wheel-edge motor are designed.Using ANSYS Workbench software,the stress and strain analysis was carried out on the spindle of wheel-side motor,and the analysis proved that the strength and stiffness requirements were met.The modal vibration of wheel-edge motor under different excitation is studied.The temperature field distribution of wheel-edge motor is studied by thermal method.By applying the method of hot way,establish the wheel edge of the motor thermal road model,in Motor CAD by electromagnetic calculation module,calculated the no-load and rated load,three kinds of motor parts in the cases of loss value,through the thermal calculation module of three kinds of working condition of motor temperature field analysis,the results show that under three conditions,the temperature of the motor are within the range of security.Machining and trial-produce the wheel edge motor prototype,and complete the basic performance test,the results meet the design requirements.