Noh Minkyun, Trumper David L
Department of Mechanical Engineering, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
IEEE Trans Ind Electron. 2020 Sep;67(9):7757-7766. doi: 10.1109/tie.2019.2942512. Epub 2019 Sep 25.
We present a new configuration of bearingless slice motor that levitates and rotates a ring-shaped solid steel reluctance rotor. The rotor is 50 mm in diameter and has salient features on the outer surface. Symmetric sets of Halbach magnet arrays, mounted on the tips of stator teeth, establish a homopolar bias flux around the rotor. The bias flux passively stabilizes the rotor in the out-of-plane tilts and axial translation, whereas the rotor's radial translations are actively stabilized by feedback control. The rotor saliencies spatially modulate the air-gap bias flux such that the resulting torque-current relationship is similar to that of permanent-magnet synchronous machines. We have designed, built, and tested a prototype bearingless motor and control system. The prototype system achieves a torque constant of 14.9mNm/A, maximum speed of 5500 rpm, and suspension bandwidth of 84 Hz with a phase margin of 11.3 deg. The rated torque and speed are 26.8 mNm and 3486 rpm, and the axial and tilting passive stiffnesses are 15.3 N/mm and 34.4 mNm/deg.
我们展示了一种新型无轴承薄片电机的结构，该电机可使环形实心钢磁阻转子悬浮并旋转。转子直径为50毫米，外表面具有显著特征。安装在定子齿尖的对称哈尔巴赫磁体阵列组在转子周围建立了一个单极偏置磁通。该偏置磁通被动地稳定转子在平面外倾斜和轴向平移时的状态，而转子的径向平移则通过反馈控制来主动稳定。转子凸极在空间上调制气隙偏置磁通，使得由此产生的转矩-电流关系类似于永磁同步电机的关系。我们设计、制造并测试了一个无轴承电机和控制系统的原型。该原型系统实现了14.9mNm/A的转矩常数、5500 rpm的最大速度以及84 Hz的悬浮带宽，相位裕度为11.3度。额定转矩和速度分别为26.8 mNm和3486 rpm，轴向和倾斜方向的被动刚度分别为15.3 N/mm和34.4 mNm/度。
