双定子无轴承开关磁阻电机径向力解析模型

Radial force analytical model of double stator bearingless switched reluctance motor

传统双绕组无轴承开关磁阻电机旋转转矩与悬浮力之间存在着复杂的耦合关系,而双定子无轴承开关磁阻电机结构上实现了转矩和悬浮力的独立控制,从而简化了控制的复杂性.基于双定子无磁阻电机的结构和运行原理,提出了一种考虑转子偏心影响的径向力分析方法,推导出了该电机的径向力解析模型.在建立内定子等效磁路的基础上,求取了由气隙磁导表示的悬浮绕组的自感和互感表达式,进一步分析出转子偏心位移、电机结构参数、悬浮绕组电流与转子径向受力之间的数学关系,与有限元分析结果比较验证了数学模型的正确性.该数学模型的重要贡献在于提供了转子偏心运行时径向力的解析计算方法,为双定子无轴承开关磁阻电机的稳定悬浮旋转控制提供了基础,同时为磁轴承和无轴承类电机转子偏心时的径向受力分析提供了参考.

For the conventional double winding bearingless switched reluctance motor （BSRM）, there is a complex coupling between torque and suspension force. But for the double stator BSRM, the torque and suspension force can be controlled independently to simplify the control complexity. Based on the structure and operating principle of the double stator BSRM, an analytic modeling of radial forces is proposed considering the rotor eccentricity. The self-inductance and mutual-inductance of the suspension windings represented by the air-gap permeance are derived u- sing the magnetic equivalent circuit of the inner stator. Furthermore, the mathematical relation- ship is derived among the rotor eccentric displacement, motor basic parameters, the suspension winding current and radial force. The built model is verified by comparing with the finite-element analysis-based results. The analytical model of the double stator BSRM provides the foundation for its stable suspension running control, which also provides a reference for the radial force anal- ysis of the rotor of the magnetic bearing and bearingless motor.