Abstract—

This article presents a novel mechanical field weakening method for flux switching permanent magnet (FSPM) machines to extend the torque-speed characteristic and improve the efficiency at high speeds. The proposed method consists of segmenting the permanent magnets (PMs) part along the back-iron radius into a circular shape embedded into the rectangular magnet. The circular-shaped magnet segments (CMSs) can then be rotated to enhance or short circuit the PMs flux. When the magnetization orientation of the PMs and the CMSs are in the same direction, the flux will flow as of that of the conventional FSPM machine, i.e. field strengthen. Conversely, when the high speed is required, the CMSs will be rotated 180°, and therefore, the PMs and the CMSs magnetization orientation will be in opposite direction, and therefore, a short circuit of the PMs flux will be created. This will lead to lower PMs flux linkage, and therefore, higher field weakening factor. A FSPM machine with 12/10 stator/rotor pole combination has been selected to investigate the proposed method. First, to study the proposed method, a comparison of the electromagnetic performance of the FSPM machine in flux strengthening and weakening states has been conducted and presented. Then, mechanical analysis of the proposed method has been made with focus on the mechanical rotating system and the consequent structural stress on the rotating magnet. In conclusion, the proposed method shown a good field weakening capability and improved torque-speed characteristics.

摘要-

本文提出了一种用于磁通切换永磁 (FSPM) 电机的新型机械弱磁方法，以扩展转矩-速度特性并提高高速下的效率。所提出的方法包括沿背铁半径将永磁体 (PM) 部分分割成嵌入矩形磁体中的圆形。然后可以旋转圆形磁体段 (CMS) 以增强或短路 PM 通量。当 PMs 和 CMSs 的磁化方向在同一方向时，磁通将像传统的 FSPM 机器一样流动，即. 场加强。相反，当需要高速时，CMSs 将旋转 180°，因此 PMs 和 CMSs 的磁化方向将在相反的方向，因此会造成 PMs 磁通的短路。这将导致较低的 PM 磁链，因此导致较高的弱磁系数。已选择具有 12/10 定子/转子极组合的 FSPM 电机来研究所提出的方法。首先，为了研究所提出的方法，对 FSPM 电机在磁通强化和弱化状态下的电磁性能进行了比较并进行了介绍。然后，对所提出的方法进行了机械分析，重点是机械旋转系统和随之而来的旋转磁体上的结构应力。综上所述，