高速永磁电机转子动力学特性分析

发布时间：2018-01-20 03:52

本文关键词： 高速电机机械强度临界转速谐响应　出处：《沈阳工业大学》2016年硕士论文　论文类型：学位论文

【摘要】：高速电机以其体积小、功率密度大等优点使其在以高速加工为代表的各场合获得普遍应用。但是,因为有高转速的特征,所以也对高速电机与从动部分的连接以及转子系统动力学特性带来了新的挑战,是以针对转子系统的动力学特性分析及研究得到业界普遍地关注。为此,根据实际需要,本文针对一台设计额定转速为30000r/min的高速永磁电动机,对其转子的机械强度进行分析,然后分析其转子及其轴承组成的转子系统的若干动力学性能,主要研究转子的不平衡量对转子动态性能的影响。首先,详细介绍等效圆环法的原理,建立等效圆环法的数学模型,用等效法对永磁体两段的内置式电机的机械强度进行分析,并与有限元法进行对比,证明等效法分析内置式电机的有效性;对在不同工作状态、不同过盈量和不同护套厚度情况下工作的表贴式电机的机械强度进行分析,确定了永磁体和护套过盈量的大小。其次,对转子系统进行模态分析并提取其固有频率、临界转速和Campbell图等模态参数。研究证实各阶模态的固有频率都远大于转子系统本身的固有频率,所以转子系统不会发生共振现象,在转速为36000r/min的情况下能够稳定运转。然后分析了不同轴承刚度等级对转子临界转速的影响,以及转子轴伸长度对电机转子系统临界转速的影响,得到轴承刚度和轴伸长度跟转子临界转速的关系曲线图。最后,对高速旋转的转子系统进行谐响应分析。分析得到转子系统在不同轴承刚度和受到不平衡力作用在不同位置时的振动响应曲线图,振动的偏移量满足电机的设计要求。
[Abstract]:Because of its small size and high power density, high-speed motor has been widely used in various situations represented by high-speed machining. However, it has the characteristics of high speed. Therefore, it also brings new challenges to the connection between high-speed motor and follower and the dynamic characteristics of rotor system, which is widely concerned by the industry by analyzing and studying the dynamic characteristics of rotor system. According to the actual needs, this paper analyzes the mechanical strength of a high speed permanent magnet motor with a rated speed of 300r / min. Then the dynamic performance of the rotor system composed of its rotor and its bearing is analyzed, and the influence of the rotor unbalance on the rotor dynamic performance is mainly studied. Firstly, the principle of the equivalent ring method is introduced in detail. The mathematical model of the equivalent ring method is established, and the mechanical strength of the built-in motor is analyzed by the equivalent method, and compared with the finite element method, the validity of the equivalent method is proved. The mechanical strength of surface mount motor working in different working state, different interference amount and different sheathed thickness is analyzed, and the size of permanent magnet and sheath interference is determined. The modal analysis of rotor system is carried out and the modal parameters such as natural frequency, critical speed and Campbell diagram are extracted. It is proved that the natural frequency of each mode is much larger than the natural frequency of rotor system itself. Therefore, the rotor system does not have resonance phenomenon and can operate stably at 36000r / min. Then, the influence of different bearing stiffness levels on the critical speed of rotor is analyzed. And the influence of rotor shaft elongation on the critical speed of motor rotor system, the relationship between bearing stiffness and shaft elongation and rotor critical speed is obtained. Finally. The harmonic response of the rotor system with high speed rotation is analyzed and the vibration response curve of the rotor system under different bearing stiffness and unbalance force at different positions is obtained. The offset of vibration meets the design requirements of the motor.
【学位授予单位】：沈阳工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TM351

【相似文献】