In this paper, the weight of the rotor is considered in a 16-pole rotor active magnetic bearing system with constant stiffness. The equations of motion are derived to show the asymmetry between the rotor’s horizontal and vertical displacements. Accordingly, the rotor may exhibit forward, backward, intermediate, or hybrid whirls. The possibility to overcome the backward whirl and to symmetrize the rotor’s motion again is discussed. Also, the rotor may rub/impact with the stator legs depending on the values of the adopted system parameters. The multiple-scales method is utilized to extract the approximate solutions of the studied model and to analyze its nonlinear dynamics and the aforementioned whirls. The discussion is enhanced by different analytical plots such as the rotor’s responses to its eccentricity \(f\) and rotation speed \(\varOmega \). Numerical validation is carried out to demonstrate how these analytical plots describe precisely the nonlinear dynamical behavior of the whole system. Finally, whirl orbit maps are plotted to simulate the real-life motion of the rotor at different whirls and at rub/impact occurrence.

在本文中，在具有恒定刚度的16极转子有源电磁轴承系统中考虑了转子的重量。导出了运动方程，以显示转子的水平和垂直位移之间的不对称性。因此，转子可表现出向前，向后，中间或混合旋转。讨论了克服后向旋转并再次对称化转子运动的可能性。同样，转子可能会与定子支腿摩擦/碰撞，具体取决于所采用系统参数的值。利用多尺度方法提取研究模型的近似解，并分析其非线性动力学和上述涡旋。通过不同的分析图（例如转子对其偏心距\（f \）的响应）来加强讨论和旋转速度\（\ varOmega \）。进行了数值验证，以证明这些分析图如何精确描述整个系统的非线性动力学行为。最后，绘制旋涡轨道图，以模拟转子在不同旋涡和发生摩擦/撞击时的真实运动。