当电机高速运行时,为避免机械磨损,采用电磁力进行悬浮支撑,而磁轴承占用轴向空间,限制临界转速。磁悬浮开关磁阻电机利用电机定子与轴承机械结构的相似性,在原有的电机定子绕组上附加一套径向力绕组,通过一定的控制策略,同时实现电机的旋转和悬浮。该文在利用有限元软件Ansoft/Maxwell 2D分析磁悬浮开关磁阻电机磁场的基础上,结合等效磁回路法并根据虚位移定理,推导出磁悬浮开关磁阻电机在考虑α、β轴方向径向偏移及其耦合时的径向力和转矩的数学模型,并用有限元分析结果验证了该模型的正确性和有效性。
Magnetic force is used to avoid mechanical friction when a motor rotates in high speed. But magnetic bearing occupies axial space and restrains the critical speed. A bearingless switched reluctance motor utilizes the similarity between the mechanical structures of magnetic bearing and motor. It adds another set of windings to switched reluctance motor in order to realize rotation and suspension simultaneously via certain control strategies. Using the finite- element analysis software Ansofl/Maxwell 2D, the magnetic field of bearingless switched reluctance motors is analyzed. According to the magnetic equivalent circuit and the theory of virtual displacement, the mathematic model of bearingless switched reluctance motors is derived when the displacement of axis αβ and its coupling are considered. The validity of the model is verified by the results of the finite-element analysis.