异步电机的故障特征分析和诊断方法研究

发布时间：2018-02-04 22:26

本文关键词： 异步电机故障诊断多回路分析小波分析　出处：《中南大学》2014年硕士论文　论文类型：学位论文

【摘要】：异步电机以其结构简单、价格低廉、可靠性高的优点,在现代工农业生产、交通运输、国防工程和人们的日常生活中取得了广泛应用。异步电机发生故障不仅会损坏电机本身,严重时还会使电机突然停机、生产线崩溃,造成巨大的经济损失和灾难性后果。因此,开展对异步电机故障特征和诊断方法的研究,有着十分重要的价值。本文针对异步电机的故障诊断研究,主要完成了以下工作：分析了异步电机的多种故障诊断方法,比较了各种方法的优缺点。从异步电机的工作原理和基本电磁关系出发,对定子匝间短路和转子断条故障的特征机理进行了分析。在精确计算定转子绕组电感参数的基础上,分析了电感大小与谐波的关系。建立了异步电机的多回路模型。在故障特征机理分析的基础上进行了异步电机故障仿真研究,比较了电机正常工作与定、转子故障时的定子电流波形较明显的特征,分析了转子断条根数与一种新的定子电流故障特征量的关系。以小波分析理论为基础,比较了多种小波分析方法在信号降噪中的应用,提出了一种基于小波包能量阈值分段的异步电机故障信号消噪方法。针对从负载波动状态下的电机定子电流信号中不利于提取出转子故障特征的问题,研究了Hilbert变换对定子电流信号的解调特性,并考察了应用小波分析判断负载波动和断条故障的可行性,提出了基于小波变换系数和Hilbert解调的转子故障诊断方法。仿真验证和电机实测信号分析的结果证明,上述方法能有效地对故障运行状态下的电机定子电流信号进行消噪,并能从负载波动的电机定子稳态电流中提取出转子故障特征量,从而对转子断条故障进行准确有效的诊断。图43幅,表4个,参考文献61篇。
[Abstract]:Because of its simple structure, low price and high reliability, asynchronous motor is widely used in modern industrial and agricultural production, transportation and transportation. National defense engineering and people's daily life have been widely used. Asynchronous motor failure will not only damage the motor itself, but also make the motor suddenly shut down and the production line collapse. Therefore, it is of great value to study the fault characteristics and diagnosis methods of asynchronous motor. In this paper, the main work of fault diagnosis of asynchronous motor is as follows: This paper analyzes various fault diagnosis methods of asynchronous motor, compares the advantages and disadvantages of each method, and sets out from the working principle and basic electromagnetic relation of asynchronous motor. The characteristic mechanism of stator inter-turn short circuit and rotor bar breakage is analyzed. The inductance parameters of stator and rotor windings are calculated accurately. The relationship between inductance and harmonic is analyzed, and the multi-loop model of induction motor is established. Based on the analysis of fault characteristic mechanism, the fault simulation of asynchronous motor is carried out, and the normal operation and setting of induction motor are compared. The characteristic of stator current waveform in rotor fault is obvious. The relationship between rotor broken root number and a new stator current fault characteristic quantity is analyzed. Based on the theory of wavelet analysis, the applications of various wavelet analysis methods in signal noise reduction are compared. This paper presents a method of de-noising fault signal of asynchronous motor based on wavelet packet energy threshold, aiming at the problem that it is difficult to extract rotor fault characteristics from stator current signal of motor under load fluctuation. The demodulation characteristics of stator current signal based on Hilbert transform are studied, and the feasibility of using wavelet analysis to judge load fluctuation and broken bar fault is investigated. A rotor fault diagnosis method based on wavelet transform coefficient and Hilbert demodulation is proposed. The method can effectively remove the noise of motor stator current signal under the condition of fault operation, and can extract the rotor fault characteristic quantity from the steady state current of the motor stator under the load fluctuation. Thus, accurate and effective diagnosis of broken bar fault of rotor is carried out. 43 figures, 4 tables, 61 references.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM343

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