感应型无轴承电机磁悬浮力解析模型及其反馈控制

由于负载、干扰和径向位移检测误差，无轴承电机悬浮运行时定、转子中心并不重合，产生偏心，影响了其稳定悬浮控制性能。该文从运行原理出发，建立了计及定、转子定位偏心的感应型无轴承电机磁悬浮力的较精确解析模型，采用电机电磁场分析软件ANSOFT验证了它的精度。应用这个模型实现了悬浮力的实时观测，在传统气隙磁场定向矢量控制系统基础上添加了悬浮力的闭环控制，有效地提高了感应型无轴承电机稳定悬浮运行的动、静态性能。

ANALYTICAL MODELING AND FEEDBACK CONTROL OF THE MAGNETIC LEVITATION FORCE FOR AN INDUCTION-TYPE BEARINGLESS MOTOR

Due to the load disturbance and detecting error of radial displacement, the centers of stator and rotor of a bearingless motor do not coincide with each other in practical operation, which will influence the control performance of stable suspension. Based on its operation principle, a relatively accurate analytical expression of the magnetic levitation force for an induction-type bearingless motor is proposed in this paper with the eccentricity in the location of stator and rotor taking into consideration, and its computation accuracy is verified by ANSOFT, an electro-magnetic field analysis software of electrical machines. Applying this analytical levitation force model, the real-time observation of magnetic levitation force can be realized, the closed-loop control of levitation force is then implemented on the basis of air-gap-flux-oriented decoupling control system of the bearingless motor. Simulation study verifies the effectiveness of the approach in improving the static and dynamic performance of an induction-type bearingless motor.