动压气体轴承支承的高速永磁电机具有高功率密度、小体积、高效率和无油等优点，目前已广泛应用于透平压缩机、燃气轮机和鼓风机等领域。由制造装配误差引起的定转子不同轴以及箔片的自适应变形等因素，都会造成转子偏心，从而产生不平衡磁拉力。因此在实际应用中，动压气体轴承支承的高速电机转子系统除了受到气膜力、不平衡质量力作用外，还会受到不平衡磁拉力的作用。针对这类轴承-转子系统，为了考察其动力学特性，揭示多场耦合的振动机理，本文将研究动压气体轴承的动态刚度、阻尼系数；动压气体轴承-转子系统的模态；以及磁流固耦合下的动力学响应。具体如下：

1.以动压气体轴承为研究对象，采用不同方法计算轴承的动态特性系数。首先基于摄动法对雷诺方程进行化简，采用有限差分法进行数值求解，计算不同涡动频率和不同转速下轴承的动态刚度和阻尼系数；其次利用线性振动理论，采用线性简谐激振法识别出轴承的动态刚度和阻尼系数；采用简谐激振法得到等效的动态特性系数。为后续的轴承转子系统模态分析提供了数据支撑。

2.建立动压气体轴承-转子系统动力学模型，计算系统的固有频率和振型，获得了刚性转子的平动涡动和锥形涡动固有频率，通过特征根判断系统的稳定性。采用有限元方法进行了对比验证。为轴承转子系统的动力学优化设计提供了理论指导。

3.采用时域弱耦合的轨迹法，综合考虑气膜流场、气隙电磁场、转子运动，三种因素影响下的基于磁流固耦合的轴承转子系统动力学模型。采用交替隐式迭代方法，求解系统的瞬态响应，得到了轴心轨迹。研究了转速、不平衡质量力、不平衡磁力对转子系统的影响规律。

Aerodynamic bearings supporting high-speed permanent magnet motors offer numerous advantages, such as high power density, compact size, high efficiency, and oil-free operation, and are now widely utilized in turbocompressors, gas turbines, and blowers. Factors such as manufacturing and assembly errors causing stator and rotor misalignment, and adaptive deformation of foils can result in rotor eccentricity and generate unbalanced magnetic pull. Therefore, in practical applications, high-speed motor rotor systems supported by aerodynamic bearings are subjected not only to gas film force and unbalanced mass forces but also unbalanced magnetic pull. This study investigates the dynamic stiffness and damping coefficients of aerodynamic bearings, the modal properties of aerodynamic bearing-rotor systems, and the dynamic response under magnetic-fluid-solid coupling. The specifics are as follows:

1. Focusing on the aerodynamic bearings, different methods are used to calculate the dynamic characteristic coefficient of the bearing. Firstly, the Reynolds equation is simplified using perturbation theory, and numerical solutions are obtained using finite difference methods to calculate the dynamic stiffness and damping coefficients at different whirl frequencies and rotational speeds. Next, utilizing linear vibration theory, the dynamic stiffness and damping coefficients are identified using the linear sinusoidal excitation method, and equivalent dynamic characteristic coefficients are derived from the sinusoidal excitation method, providing data support for subsequent modal analysis of bearing-rotor systems.

2. A dynamic model of the aerodynamic bearing-rotor system is developed to calculate the system's natural frequencies and mode shapes, yielding the planar and conical whirl natural frequencies of the rigid rotor. System stabilityis determined through eigenvalue analysis, and a comparative validation is performed using the finite element method, providing theoretical guidance for the dynamic optimization design of bearing-rotor systems.

3. Employing a time-domain weakly coupled trajectory method, a magnetic-fluid-solid coupling bearing-rotor system dynamic model is established, considering the combined effects of hydrodynamic flow field, air gap electromagnetic field, and journal motion. An alternating implicit iteration method is used to solve the transient response of the system, yielding the trajectory of the center of the rotor. The influence of rotational speed, unbalanced mass force, and unbalanced magnetic force on the rotor system is investigated.