高速永磁电机的永磁体和护套涡流损耗分析

Research on the Permanent Magnet and Sheath Eddy Current Loss of a High-speed Permanent Magnet Motor

应用于飞轮储能的高速永磁同步电机涡流损耗的研究对于电机可靠性具有重要意义。通过有限元仿真分别计算永磁体和护套中的涡流损耗,并重点研究高速电机护套材料电导率的不同对于高速电机转子涡流损耗的影响,以及永磁体与护套电导率的比值对转子总损耗的影响。结果表明:在选择护套时并不是导电率越小越好,只有当小于某个特定电导率时,总损耗才能降低;并且护套材料的电导率越大,其对永磁体中的涡流损耗的屏蔽效果越明显,护套材料电导率的大小,对损耗在护套和永磁体中的分布起了一定的分配作用。

It is significant for the reliability of the motor to research on eddy current loss of a high-speed permanent magnet synchronous motor (PMSM) which is used for flywheel energy storage system. The eddy current losses of the permanent magnet and the sheath are calculated respectively by finite element method (FEM). It focuses on the effect of the different conductivity of sheath materials of high-speed motor upon the rotor eddy current losses and the effect of the ratio of the conductivity of permanent magnet and the conductivity of sheath on the whole rotor losses. The results show that in order to reduce the whole rotor eddy current losses, the conductivity of sheath should not be as small as possible. Only when the conductivity of sheath is smaller than a particular value, the whole rotor losses can be reduced significantly. And the greater the conductivity of the sheath is, the more obvious the shielding effect on the permanent magnet eddy current losses is. The conductivity of the sheath plays a role in the assignment and distribution of the loss in permanent magnet and the sheath.