双并列转子永磁同步电机设计与分析OA

In parallel-to-drive mechanical equipment,such as a double screw pump,a two-high mill,and a roll crusher,the mainstream of current driving mode is single-motor master-slave driving.A single motor transmits torque to the drive shaft through the transmission links.The driven shaft is driven by the mechanical synchronous gears between the two shafts,thus achieving reverse synchronous rotation.This driving mode has several issues,including a large equipment volume,low system efficiency,significant mechanical noise,challenging sealing,and regular maintenance requirements.Additionally,the single motor drive is primarily composed of an induction motor and a gearbox transmission,resulting in significant energy loss throughout the entire transmission system.This paper proposes a novel dual-parallel rotor permanent magnet synchronous motor(DR-PMSM)for directly driving parallel-to-parallel mechanical equipment.The DR-PMSM can eliminate the redundancy of the transmission system,offering advantages such as a small system size,high system efficiency,gearless transmission,and low mechanical noise. The design method and electromagnetic characteristics of DR-PMSM are studied.The structure of DR-PMSM is described,and the new design parameters are defined.The operating principle of DR-PMSM is analyzed,and the effect of each magnetic flux path on the motor is studied.The general design process of this kind of motor is explored,and the design method and determination principle of each key link are given.On this basis,a DR-PMSM is designed,and a finite element model is constructed to analyze its electromagnetic characteristics,including the magnetic field,back electromotive force,inductance,torque,rotor electromagnetic force,and efficiency.The reasons for the asymmetry or imbalance in various electromagnetic characteristics are revealed.Additionally,the influence of key parameters on key performance is discussed,and the method for selecting and optimizing these parameters is provided.A DR-PMSM is manufactured,and a test platform is set up to verify the correctness of the proposed design method. The following conclusions can be drawn.(1)The design process of DR-PMSM is divided into three parts.The key design links of each part are the determination of the coupling angle,the selection of the main size for the single-sided conventional motor,and the optimization of key parameters.(2)The coupling area of DR-PMSM distorts the air gap magnetic field.The asymmetric phenomenon of three-phase flux linkage,back EMF,inductance,etc.,is caused by the asymmetry of the magnetic circuit in the coupling area.At the same time,the coupling area increases even harmonics in the electromagnetic torque,causing the rotor's electromagnetic force to become unbalanced.(3)Duty angle and coupling distance are the key parameters that determine the structure of the coupling area and directly affect the torque ripple and rotor electromagnetic force.The smaller duty angle is conducive to improving the key performance,and the coupling spacing needs to be selected according to the specific situation.The experimental results of the prototype demonstrate the feasibility of the proposed design method,providing theoretical guidance for the engineering application of DR-PMSM.