Basic Research Of A Novel3-DOF Deflection Type PM Motor

With the deep development process of the automation and intelligence, themovement of the actuator need to be performed is not only limited in singledegree-of-freedom (DOF) direction, but also in multi-DOF directions. The motors that arecapable of implementing multi-DOF motions have come to a novel research direction.Based on the analysis of the present research and development situation of the m-DOFmotors, a novel3-DOF deflection type PM motor is analyzed and studied which features arotor with single layer PM and a stator with two layers of circumferential core coils. Thefinite element model of the motor is established, the3D static magnetic field analysis ofthis PM rotor is carried out, the torque model of the motor is also built, the optimizationdesign of the motor is performed, and finally, an improved motor model is proposed. Forthe sake of the particular structure and application of this motor, the motor has been inresearch stage at present. The research results of this dissertation can provide significantreference to the research of similar motors. Compared with ordinary M-DOF motors, the3-DOF deflection type PM motor combines the merits of simple structure, relatively smallvolume, easy to be controlled and high-performance torque. As an operation component,this motor can realize3-DOF motions perfectly, which can simplify the complexity of thetransmission, and improve the dynamic and static performance. Therefore, this motor hasa wide prospect of application, worth to be researched in depth.The main contribution of this dissertation can be discussed as follows:1) The structure and size of the3-DOF deflection type motor is introduced in detailas well as the fundamental operating principle. The three-dimensional finite elementmodel of this3-DOF deflection type PM motor is established by Ansoft Maxwell3D, andthe modeling method of this software has been explained roughly. The computed resultsof finite element method are summarized.2) The PM rotor has three ways of magnetization according to its particular structure.The inner and surroundings static magnetic field of PM rotor has been analyzed in form ofcomparing the three magnetization methods. The influence of the height and thickness ofthe rotor with respect to the magnetic flux density is analyzed.3) The safety range of stator coils’ electromotive force exerted has been confirmedaccording to copper wire’s safe current carrying capacity. The electrical magnetic field of winding has been quantitatively analyzed in detail. The dynamic magnetic field of rotorand stator of the motor was computed when it moves in three axes respectively.4) Based on the analysis of the mechanism of the torque production of the3-DOFdeflection type PM motor, the torque characteristic was simulated by finite elementmethod, and the influences of the structure parameters on the torque is analyzed. A controlstrategy of the motor is proposed. In order to validate the accuracy of the finite elementmethod, an analytical method for torque analysis is applied, the results produced byanalytical method and finite element method are basically in agreement.5) Based on the analysis of the mechanism of the torque production of the3-DOFdeflection type PM motor, the torque characteristic was simulated by finite elementmethod, and the influences of the structure parameters on the torque is analyzed. A controlstrategy of the motor is proposed. In order to validate the accuracy of the finite elementmethod, an analytical method for torque analysis is applied, the results produced byanalytical method and finite element method are basically in agreement.