高磁路饱和永磁同步电机永磁体负载磁链动态估算

Dynamic Estimation of Permanent Magnet Load Flux Linkage of Permanent Magnet Synchronous Motor with High Magnetic Circuit Saturation

永磁同步电机通常由于安装空间和自重的限制,要求其具有较高的电、磁负荷,导致电机内部出现严重的磁路饱和,而在高磁路饱和的情况下,永磁体磁链会随电流的改变而发生非线性变化。为了准确估算电机负载状态下的永磁体磁链,该文首先描述了dq轴电流对永磁体磁链的影响,并结合定子铁心局部磁饱和特性,分析了气隙磁动势和铁心磁动势之间的比例关系,提出了基于磁链系数的永磁体磁链模型。接着根据测量的相电压以及定子铁心材料的磁导率曲线,提出了一种考虑磁路饱和的永磁体负载磁链动态估算方法。最后搭建了300kW内置式永磁同步电机实验平台,通过有限元仿真和实验验证了该文所提出的估算方法的有效性和准确性。

Due to the limitation of installation space and self-weight,a permanent magnet synchronous motor(PMSM)usually requires high electrical and magnetic loads,resulting in severe magnetic circuit saturation.Under the condition of high magnetic circuit saturation,the flux linkage of the permanent magnet(PM)changes nonlinearly with the change of current.In order to accurately estimate the PM flux linkage of the motor under load conditions,this paper first describes the influence of the dq-axis currents on the PM flux linkage.Combined with the local magnetic saturation characteristics of the stator core,the proportional relationship between the air gap magnetomotive force and the core magnetomotive force is analyzed.Then,a model of PM flux linkage based on the flux linkage coefficient is proposed.After that,according to the measured phase voltage and the permeability curve of stator core material,a dynamic estimation method of PM load flux linkage considering magnetic circuit saturation is proposed.Finally,a 300kW interior PMSM test platform is established,and the effectiveness and accuracy of the estimation method are verified by finite element simulation and tests.