高速永磁起动发电机轴承—转子系统的动态特性研究

发布时间：2018-07-23 07:54

【摘要】：对于旋转机械,尤其是转速远高于一阶临界转速的高速转子,轴承—转子系统的临界转速等固有的性质,会影响旋转机械的平稳性。影响平稳性的最普遍的问题是振动问题,转子系统大幅振动,不但影响高速永磁起动发电机的性能,还可能出现各种事故,导致高速永磁起动发电机不能正常工作。本文中所要研究的高速永磁起动式发电机,其转速要求达到每分钟十万转左右,工作转速远远高于一阶的临界转速,将其作为刚性轴进行研究已经不能达到预期的效果,因此要将转子作为挠性轴进行动态特性分析。本文以转子动力学作为基础的理论,建立了传递矩阵法计算临界转速的模型;同时使用该改进的Riccati传递矩阵法,解决了漏根、错根的问题;借助于Pro/E、MATLAB、ANSYS等软件进行了模型参数的计算,编制了计算临界转速和模态振型的程序;通过对文献算例的验证,证明了程序的正确性;在MATLAB的基础上,对动力学软件的设计进行了初步的尝试;设计了简单的可视化界面。在影响临界转速的因素中,对轴承支座的刚度和轴承的刚度两个方面进行了分析,其中轴承的刚度又从轴承预紧力、接触角、转子转速三个方面进行了分析。对高速永磁起动发电机使用动刚度进行了临界转速、模态振型的计算。在理论分析的基础上,对轴承支座进行了力锤的瞬态激振实验,从中分析出轴承支座的固有频率、轴承支座刚度等模态参数;对轴承正常工作时进行了动态信号的采集,分析了高速永磁起动发电机运转过程中产生振动的原因,从实时频谱中找出了高速永磁起动发电机的临界转速;从实验得出了临界转速随轴承预紧力的变化规律;根据变化规律提出了调整临界转速的措施。最后在以上分析的基础上,对刚性联轴器—转子系统、挠性联轴器—转子系统的临界转速进行了分析比较。
[Abstract]:For rotating machinery, especially for high speed rotors whose rotational speed is much higher than the first order critical speed, the critical speed of the bearing-rotor system will affect the smoothness of the rotating machinery. The most common problem affecting the stability is vibration. The large vibration of rotor system not only affects the performance of high speed permanent magnet starter generator, but also may occur various accidents, resulting in the high speed permanent magnet starting generator can not work normally. In this paper, the speed of the high speed permanent magnet starter generator is required to reach about 100, 000 revolutions per minute, and the working speed is much higher than the first order critical speed. Therefore, the rotor should be used as a flexible shaft to analyze the dynamic characteristics. Based on the theory of rotor dynamics, the transfer matrix method is used to calculate the critical rotational speed, and the improved Riccati transfer matrix method is used to solve the problem of leakage root and wrong root. With the help of Prop / EMA MATLAB ANSYS and other software, the calculation of the model parameters is carried out, and the program for calculating the critical rotational speed and modal mode is compiled, and the correctness of the program is proved through the verification of an example in the literature. The design of dynamic software is tried and a simple visual interface is designed. Among the factors affecting the critical rotational speed, the stiffness of bearing support and bearing are analyzed, and the stiffness of bearing is analyzed from three aspects: bearing preload, contact angle and rotor speed. The critical rotational speed and modal mode of the high speed permanent magnet starter generator are calculated. On the basis of theoretical analysis, the transient vibration test of the bearing support is carried out, from which the modal parameters such as the natural frequency and the stiffness of the bearing support are analyzed, and the dynamic signals are collected when the bearing is working normally. In this paper, the cause of vibration of high speed permanent magnet starter generator is analyzed, the critical speed of high speed permanent magnet starter generator is found out from the real time spectrum, and the variation rule of critical speed with bearing preload force is obtained from the experiment. According to the law of change, the measures to adjust the critical speed are put forward. Finally, the critical speeds of rigid coupling rotor system and flexible coupling rotor system are analyzed and compared on the basis of the above analysis.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH113.1

【参考文献】