新型同步磁阻电机星形转子结构设计与分析

Astroid rotor structural design and analysis of a synchronous reluctance motor

针对同步磁阻电机转矩脉动大、平均转矩低的问题,提出一种星形转子结构,该结构与传统圆形转子结构相比,增大了转子气隙磁障末端与q轴的夹角,改变了气隙磁密的分布,可以减小转矩脉动,增大输出转矩。描述了星形曲线的形成过程,推导了星形曲线方程,得到参数方程参数角与磁障末端角的数学关系,为后续研究提供理论基础。基于等效磁路法建立了气隙磁密模型,进而可以得到转矩预测模型,并通过解析法和有限元进行对比,验证了磁路模型的有效性与正确性。通过有限元仿真,对星形转子结构同步磁阻电机和传统圆形转子结构同步磁阻电机进行性能对比分析,结果表明前者的铁耗小,气隙磁密波形谐波畸变率小,正弦化程度高,输出转矩大及转矩脉动小,验证了星形转子结构的可行性。

To solve the problem of large torque ripple and low average torque of synchronous reluctance motor,an astroid rotor structure is proposed.Compared with the traditional circular rotor structure,this structure increases the angle between the end of rotor air gap magnetic barrier and the q-axis,changes the distribution of air gap magnetic density,reduces torque ripple and increases output torque.In this paper,the formation process of astroid curve was described,the equation of astroid curve was derived,and the mathematical relationship between the parameter angle of the parameter equation and the end angle of the magnetic barrier was obtained,which provided a theoretical basis for subsequent research.The air gap magnetic density model was established based on the equivalent magnetic circuit method,and then the torque prediction model was obtained.The validity and correctness of the magnetic circuit model were verified by comparing the analytical method through finite element method.Through finite element simulation,the performance of astroid rotor synchronous reluctance motor and traditional circular rotor synchronous reluctance motor was compared and analyzed.The results show that the former has small iron loss,high degree of sinusoidal air gap magnetic density waveform,low harmonic distortion rate,large output torque and small torque ripple,which verifies the feasibility of astroid rotor structure.