The nonlinear radial forces relationship regarding phase currents and rotor angle demands a nonlinear control structure for bearingless motors. Most state-of-the-art control algorithms of bearingless motors are based on the assumption of linear current to force/torque relationship, and only the nonlinear relationship to the rotor angle is taken into account. However, in some types of bearingless motors, especially in motors with reluctance-type rotor, suspension forces are quadratic functions of the phase currents, which means that, in addition to linear terms, quadratic terms also contribute significantly to force generation. In this article, a novel control structure is presented, which allows controlling a bearingless motor featuring significant nonlinear current to force/torque relationship. Digital signal processor implementable solution was found by a numeric solution followed by the second-order Taylor approximation. To check the functionality, the suggested control structure was implemented with a bearingless flux-switching 12/10 motor.

中文翻译：

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组合绕组系统的无轴承磁通片式电动机的非线性控制

关于相电流和转子角的非线性径向力关系需要用于无轴承电动机的非线性控制结构。大多数无轴承电动机的最新控制算法都是基于线性电流与力/转矩关系的假设，并且仅考虑与转子角的非线性关系。但是，在某些类型的无轴承电动机中，尤其是在具有磁阻型转子的电动机中，悬架力是相电流的二次函数，这意味着，除了线性项外，二次项也显着地影响了力的产生。在本文中，提出了一种新颖的控制结构，该结构允许控制具有显着非线性电流与力/转矩关系的无轴承电动机。通过数字解和二阶泰勒逼近找到了数字信号处理器可实现的解决方案。为了检查功能，建议的控制结构是通过无轴承磁通切换12/10电动机实现的。