Design And Analysis Of Direct-Drive Hybrid-Excitation Flux-Switching Machine For Oil Production

While renewable energy is an effective way to cope with energy crisis and solve environmental problems,petroleum is still playing an significant role in social process,and pumping unit is also playing an important part in the petroleum extraction system.However,the existing pumping units suffer from the disadvantages of wide torque range,low efficiency and complex transmission structure,hence,based on the conventional flux-switching permanent magnet(FSPM)machine,which can offer the merits of low-speed high-torque direct-drive capability and high efficiency,adopting hybrid-excitation scheme to meet the requirement of wide torque range of pumping units,a novel axial partitioned stator hybrid-excitation flux-switching(APS-HEFS)machine is proposed,and this paper focuses on the following research on the proposed machine.1.Based on the classical 12-slot/10-pole FSPM machine topology,adopting axial partitioned stator structure,a novel axial partitioned stator hybrid-excitation flux-switching machine is proposed in this paper,with the field-excitation windings and armature windings placing on field-excitation stator and armature stator,respectively.Then,the magnetic path and flux regulation principle are analyzed.2.In order to obtain the optimum performance of the proposed machine,the influences of the structure and key parameters of the stator and rotor on the electromagnetic performance are investigated by finite element analysis,and the optimum design parameters of the proposed machine were finally acquired.3.Three-dimensional finite element analysis of the proposed machine is carried out,and the static characteristics of it are calculated,including the magnetic field distribution,no-load flux linkage,no-load air-gap flux density,no-load induced electromotive force,cogging torque and electromagnetic torque.Then,the comparison of two HEFS machines is assessed,based on which the advantages and disadvantages of the proposed machine are analyzed.4.On the basis of the proposed machine,combined with the research status of electric machine loss calculation,especially iron loss calculation,the theoretical calculation models of magnetic flux density on stator and rotor cores and core loss of the proposed machine are established,and the results of magnetic flux density calculation and iron loss calculation are verified through three-dimensional finite element analysis.Finally,the calculation results are analyzed.