Design And Performance Analysis Of Six-phase Axial Flux Permanent Magnet Motors With Double-stator Dislocation

The drive motor,as a vital component of the main drive system,has recently attracted the extensive attention of university and corporate researchers with the fast advancement of new energy electric motorcycles.Compared with the three-phase radial flux permanent magnet motor,the asymmetric six-phase axial flux permanent magnet motor,which is well suited to the application of the new energy electric motorbike drive motor,combines the compact structure and high torque density of the axial flux permanent magnet motor with the low torque pulsation and high fault tolerance performance of the multi-phase motor.A unique dislocated six-phase structure based on a double-stator single-rotor axial flux permanent magnet motor is proposed in this thesis,breaking through the constraints of traditional six-phase motor pole/slot combinations.The following elements are primarily investigated and analyzed:Firstly,a six-phase axial flux permanent magnet motor with a double stator dislocation structure is presented to investigate the building criteria for a six-phase motor.A quasi-3D subdomain analytical model is constructed utilizing the exact subdomain approach to quickly analyze the properties of the motor air gap magnetic field.The analytical model can take into account the impact of the teeth tips and the arbitrary dislocation angles.The influence of permanent magnet size on the motor air gap magnetic field is investigated using the subdomain analytical model to offer the theoretical foundation for further motor design.Second,the feasibility and precision of a double-stator dislocated six-phase axial flux permanent magnet motor are validated using finite element software,employing the major dimensional equations and analytical models.To investigate the superiority of dislocated sixphase motors,the magnetic field distribution,no-load and load performance of symmetrical three-phase motor and dislocated six-phase motor are compared and analyzed.The maximum torque output and weak magnetic speed regulating capabilities of the two motors,as well as the danger of irreversible demagnetization,are compared and analyzed.The benefits and drawbacks of dislocated six-phase axial flux permanent magnet motors are studied in further depth.Next,the cogging torque of a double-stator dislocated six-phase axial flux permanent magnet motor is investigated.The analytical equation for the cogging torque of a double-stator dislocated axial flux PM motor is obtained based on the energy method,as well as the impact of the dislocation angles and pole/slot combinations on the double-stator dislocated axial flux permanent magnet motor.Finally,the influence of dislocated six-phase motors on permanent magnet eddy current losses is investigated.The dislocated six-phase motor’s diminished impact on harmonic is validated by comparing and evaluating the diminishing effects of three-phase motor,singlestator coexisting six-phase motor,and dislocated six-phase motor on permanent magnet eddy current losses.