Research On Topology And Electromagnetic Characteristics Of Flux Switching Permanent Magnet Machine

Flux Switching Permanent Magnet Machine(FSPM)has high efficiency,high power and excellent speed regulation performance,and can quickly respond to changes in load demand.Therefore,FSPM machines have broad application prospects in industrial production,transportation and other fields.In this paper,the analytical expressions of air gap flux density and cogging torque of FSPM machine are derived,and two novel FSPM machine topologies are proposed.In addition,the design parameters of the novel topology are optimized,and the electromagnetic performance is compared with the traditional model.The specific work is as follows:Firstly,based on the principle of magnetic field modulation,the expression of air gap flux density of traditional 12/10-pole FSPM machine under no load reaction and armature reaction is derived,and the modulation effect of salient pole shape rotor teeth on air gap harmonics of FSPM machine is analyzed.By analyzing the interaction of harmonics under permanent magnet magnetic field and armature magnetic field,the mechanism of torque generation of the machine is expounded,and the correctness of the analytical expression is verified by finite element analysis.Secondly,the analytical expression of cogging torque of FSPM machine is derived by combining energy method and Fourier decomposition method,and the structural factors affecting the cogging torque of the machine are summarized and analyzed.A novel 12/10-pole FSPM machine is proposed.The permanent magnet and magnetic bridge with radial magnetization are introduced to reduce the cogging torque amplitude of the FSPM machine.The electromagnetic performance of the traditional machine and the novel machine is calculated and compared.Thirdly,a MT-FTFSPM machine with high temperature superconducting bulk is proposed.The magnetic flux leakage of stator yoke is reduced by unilaterally embedded radially magnetized permanent magnets,and the magnetic flux leakage of stator teeth is reduced by using the magnetic flux shielding effect of high temperature superconducting materials,thereby improving the torque performance of the machine.The output torque and self-inductance mutual inductance ratio of the traditional topology and the novel topology are compared and analyzed in the finite element method.Fourthly,the multi-objective genetic algorithm(MOGA)is used to optimize the above two novel topologies.The parametric model of the novel topologies is established,the design parameters of the radially magnetized permanent magnet and the magnetic bridge on the stator structure are optimized,and the electromagnetic performance of the optimized machine is verified in the finite element.