Design And Analysis Of Axial Flux Motor For EVTOL Aircraft

In recent years,electric vertical take-off and landing（e VTOL）aircraft have attracted much attention.Compared with the traditional fuel engine drive system,the motor drive system has the advantages of simple structure,short take-off and landing distances,and low operating costs.For the aircraft with good performance,the selection of motor is particularly important.The common radial flux motor in the market has shortcomings,so the structure of axial flux motor is studied and analyzed,and a motor with high efficiency and low loss is designed,which requires small cogging torque,so as to avoid the impact of noise and vibration.In this paper,the axial flux motor with double rotor and single stator structure is determined to be used in electric vertical takeoff and landing vehicles with special requirements for motor structure.Two different types of axial flux permanent magnet synchronous motors are designed by calculating the performance parameters of the motor and the relevant dimensions of the stator and rotor,and the design of the motor structure and electromagnetic scheme are determined.Using the finite element software ANSYS Maxwell,the working conditions of two kinds of motors under static and transient fields are analyzed,and the waveforms such as magnetic density cloud diagram,magnetic circuit structure and back EMF of the motor,torque simulation and loss simulation waveforms under load are obtained,which verifies the feasibility of the designed motor.In view of the influence of torque ripple on the smooth operation performance of the motor,the Taguchi method is used to optimize the motor design,the cogging torque and torque ripple are optimized,and the permanent magnet and air gap are selected as the optimization parameters to verify that the motor performance is improved after optimization.In addition,the performance of the coreless axial flux motor in the double closed-loop control system is also studied,and the effect of the sine wave driving mode on the motor is discussed.Using sliding mode observer instead of sensor system,the speed,rotor position,torque and current waveform are obtained,and the corresponding control system is constructed.The experimental results show that the motor parameters designed in this paper are reasonable and effective.