双凸定子极无轴承开关磁阻电机数学模型

Mathematical Model of Bearingless Switched Reluctance Motors with Double-Salient Stators

双凸定子极无轴承开关磁阻电机可实现悬浮力和转矩的解耦,控制简单,具有应用优势。但该结构电机在悬浮绕组与转矩绕组同时导通时,非导通相齿极中存在较大的磁通,该磁通不可忽略,磁通分布较为复杂,给数学模型的建立带来了困难。根据电机的磁通分布建立了等效磁路图,依据虚位移法推导了悬浮力数学表达式。同时根据电机转矩与悬浮力之间的解耦特性,给出了电机转矩公式。为了验证所提数学模型的合理性,进行了有限元仿真验证,结果表明数学模型与仿真值具有较好的一致性。

Bearingless Switched Reluctance Motors （BSRM） with double-salient stators feature the decoupling between torque and radial force, which results in simpler motor control. So the novel BSRM has the advantage in the industrial ap- plication. However, a considerable amount of flux exists in the non-energized phase poles with descending inductance when the suspending and torque coils are conducted simultaneously and this much complicates the flux distribution. This makes the derivation of motor＇ s mathematical model difficult. Set up an equivalent magnetic circuit based on the flux distribution and further derives the formula of suspending force by virtual displacement method. At the same time, the motor＇ s torque was also formulated in which the decoupling of the torque and force was considered. To show the accuracy of the proposed model, a series of FEM analysis are conducted and the results well verify the agreement of simulation with theoretical values.