Design And Optimization Of Star Rotor Structure Of Synchronous Reluctance Motor

Due to the advantages of simple rotor structure,low loss and low cost,the application prospect of synchronous reluctance motor is more and more broad,and it is widely used in pumps,textile machines and other industries.Therefore,the research on the performance and optimization of synchronous reluctance motor has practical engineering value.The performance of synchronous reluctance motor is greatly affected by the rotor structure,so one of the key points of studying synchronous reluctance motor is the design and optimization of rotor structure.In order to improve the performance of synchronous reluctance motor,a star rotor structure(which is different from the traditional circular rotor structure,segmented rotor structure and fluid rotor structure)is proposed in this paper.The star rotor structure synchronous reluctance motor is designed and analyzed,and then the salient pole ratio is optimized by using beetle antennae search-particle swarm optimization algorithm to improve the torque performance of synchronous reluctance motor.Firstly,the mathematical model of synchronous reluctance motor is introduced.The salient pole ratio model is established by analyzing the d-q axis magnetic circuit.Combined with the engineering practice and theoretical analysis,the initial values of the stator slot,air gap,rotor magnetic barrier layers,magnetic barrier thickness,tangential rib thickness and other parameters of synchronous reluctance motor are determined.The circular rotor structure is determined as the comparison object,which provides the theoretical basis for the subsequent performance comparison and analysis.Secondly,in order to improve the torque performance of the motor,the star rotor structure of synchronous reluctance motor is proposed,and the mathematical derivation of the star structure curve is carried out.The relationship between the end angle of the magnetic barrier and the star line parameter angle is derived,and then the mathematical relationship between the thickness of the magnetic barrier and the end angle of the magnetic barrier can be derived,which provides a theoretical basis for the establishment of the subsequent air gap magnetic density model and the optimization of the motor.Then the air gap magnetic circuit of synchronous reluctance motor is analyzed based on the equivalent magnetic circuit method,and the air gap magnetic density model is established.The correctness of the model is verified by comparing the finite element method with the analytical method.Taking the circular rotor synchronous reluctance motor as the comparative object,the magnetic density,iron loss and torque of the star rotor synchronous reluctance motor are analyzed and feasibility and effectiveness of the proposed star rotor synchronous reluctance motor is verified.Finally,because there are many constraints in the optimization of synchronous reluctance motor,and the traditional optimization algorithms(such as genetic algorithm,particle swarm optimization,etc.)are prone to fall into local optimization or premature,the hybrid algorithm of beetle antennae search-particle swarm optimization is introduced into the optimization of synchronous reluctance motor.The hybrid algorithm not only has the fast convergence of longicorn whisker algorithm,but also has the swarm optimization ability of particle swarm optimization.It can solve the multi constraint optimization problem well and reduce the possibility of falling into local optimization.A total of six variables to be optimized,including three magnetic barrier end angles and three magnetic barrier thicknesses,are selected in the salient pole ratio model.With the salient pole ratio as the optimization objective,the air gap magnetic density,torque,stress and deformation of the optimized model are analyzed,which verifies the effectiveness of the beetle antennae search-particle swarm optimization algorithm in the optimization of synchronous reluctance motor.