毕业论文 基于DSP技术为机车轴承设计故障诊断监控系统 英文翻译

原文：

Design of Fault Diagnosis Monitor System for the Locomotive

Bearings Based on DSP Technology

Abstract

The rolling bearing is one of the key parts of the locomotive running components, because it condition is directly related to the performance and safety of locomotive. In this paper, the monitor system for the locomotive bearings based on DSP TMS320LF2407A is designed. This system diagnoses the rolling bearing fault using vibration analysis method. It is based on comprehensive resonance demodulation and fast Fourier transform technique, and it adopts "related methods" to handle the result of the FFT. It effectively improves the response characteristics, sensitivity, differentiate and measurement accuracy of the bearing failure monitor system, and it can fulfill the monitor and prediction of the transient fault in the course of the locomotive running.

Key words: resonance demodulation technology; digital signal processor; related methods

I. Introduction

The higher safety is required to the trains because its speed is raised constantly. Bearing fault is one of the major factors causing eventful traffic accidents and affecting rail safety. Currently the railway system usually uses the bearing temperature detector to monitor the locomotive bearing condition. Theoretical analysis and a lot of practice show that the bearing temperature detector can prevent accidents from occurring to some extent, but most of the bearing fault is not sensitive to temperature. When the temperature of the bearing is beyond the range and the system gives an alarm, the worse damage of the bearing has occurred, and even the

incident had happened. Therefore, to find the fault more early and accurately, the more advanced monitoring means must be adopted. Most of the bearing fault is very sensitive to vibration signal. The fault can cause vibration of the bearing increased. Compared with monitoring the temperature of bearing, the analysis and processing results to the vibration signal has more advantage than the temperature means.

II. System composing and work process

Based on the need, the monitor of the bearing fault monitoring system to the locomotive bearing sets two detections: itineration detections and fixed detections. The itineration detection is used in the normal conditions, and the fixed detection is used for the continuous monitoring of the fault bearing. The system adopts special composite sensor to collect the vibration of the bearing and the temperature signal at the same time. After the data processing, the corresponding fault levels and rise in temperature are got. The data acquisition unit is designed in this system. Alarm information will be transmitted to all carriages through interfaces so that the staff can handled in time, and the same time, the fault data and the related information of the train such as the current location and speed will be transmitted to the dispatch center through GPS, which is convenient to adopt corresponding measures. The system block diagram is in Fig. 1.

III. The key technology of the design for the monitoring system

A.The spectrum analysis means for diagnosing bearing fault

Under normal circumstances, all parts of the rolling bearing (inner circle, outer circle, roller, holding frame) will retain the stable relative movement state. If the surface of some element (except for holding frame) has crack, and this crack is in the surface of the rolling adjacent component, the instantaneous vibration impulse must be produced.

Assumed that the number of the roller in the bearing is Z ; the diameter of the roller is d ; the average diameter of the bearing inner circle and the bearing outer circle (the diameter of the roller revolution path) is D ; the frequency of the bearing rotation is f 0. Assumed that the inner circle is fixed and the outer circle is circumvolved, the vibration frequency brought by the surface defects of different bearing components can be derived.

These frequencies can be called the fault characteristics frequency of the inner circle, outer circle and the roller.

()circle)

(inner 2101f D d Z f += ()circle)(outer 2101f D d Z f -=

()(roller)]1[021f D d d D f -=

B. Resonance demodulation technology

We can collect vibration signal using the resonance of the bearing components, and detect the envelope of the fault signal using envelop detector, which can fulfill the analysis to the fault character. This is called “resonance demodulation

technology”. The component surfaces such as the inner circle, the outer circle and the roller of the rolling bearing are easily damaged in local place in the course of operation (such as pitting and peeling off, cracking, scratching etc.). If the surface of some bearing components have local damage and the rollingobject presses the fault dot in the course of carried operation, it must bring impact. But the impact lasts a short time, and the frequency range of the energy divergence is wide, so the energy within the scope of vibration frequency is small. Due to the wide bandwidth of the impulse, it is certainly that it includes high frequency intrinsic vibration inspiring by intrinsic frequency of the inner circle, outer circle, roller, holding frame on rolling bearings. The resonance demodulate signal is separated by band-pass filter of center frequency equal to its intrinsic frequency. Then the envelope demodulation is carried through to there attenuation oscillatory wave using software or circuit, the frequency component of the high frequency attenuation vibration is wiped off. We only obtain low-frequency envelope signal with the information of the fault character. The spectrum analysis of the envelope signal is carried through by digital signal processor, we can obtain very high frequency resolution ratio and can easily find the frequency of the corresponding fault impact, thereby we can fulfill to diagnose to the bearing fault.

With resonance demodulation technology, the electric resonator which resonant frequency is much higher than normal vibration frequency and limited high-harmonic frequency is designed. Therefore, it can effectively restrain the low-frequency signal including normal vibration signal. The resonance response magnifies the signal amplitude of the impulse signal and the time of its oscillation islonger, thus the fault signal is broadened in the time domain signal. After the envelope detection and low-pass filter, the low-frequency resonance demodulation signal with high signal-to-noise ratio is exported. In the signal processing system shown in figure 2, the bearing component brings resonance under the impact, form the continuo us attenuation oscillation. To research each attenuation oscillation, we can see that its frequency is the natural frequency of bearing components, the amplitude of attenuation oscillation is relate to intensity of fault impact. The amplitude of envelope

signal of the attenuation oscillation reflects the size of the fault, and the repeat frequency of the envelope depends on the fault location. System has the performance of anti-jamming of the low frequency vibration, high signal-to-noise ratio.

C. Envelope detection

A bearing with fault in the course of rolling will bring regular vibration. Different fault has different character frequency. The character frequency system detecting is the frequency of the signal envelope (the frequency which is accrued by the collision of the fault on bearing element), not the vibration frequency of the bearing. When we analyze the fault signal, the resonant frequency (carrier wave) must be removed by envelope demodulation. Because the envelope signal has fully included all information of the fault, removing carrier wave will not have any adverse impact on the analysis.

IV. Hardware and software design

The hardware block diagram of the monitor for the bearing fault is shown in Fig.

3.

The circuit includes two parts: the vibration signal pretreatments and the bearing state analysis. The signal preprocessing part fulfills the amplification, conversion, resonance demodulation of the signal; the bearing state analysis part fulfills spectrum analysis of the signal, "correlation method" processing, fault grading processing, the

bearings status report and communicating with peripheral equipment and so on.

There are mainly three kinds of FFT algorithm to realize in DSP: (1) only including addition and subtraction operations without operations of the plural rotation factor; (2) including the operation of the plural rotation factor; (3) the operation of bits location inversion. After data is processed by this way, the workload of vibration component calculation in DSP is reduced evidently. The real-time capacity of system response can be advanced.

Modularization design is adopted in the design of the software, which includes collections of the vibration signal and the temperature increment signal, A/D conversions, data pretreatments, FFT transforms, calculations of the power spectrum, judgments of the fault grading, saves of the data, displays of the data and transmissions of the data. The task dispatch is carried through by the way of event triggers and time triggers. To remove the interference, the “correlation means” processing to the results of FFT transform is carried out, which assure the fault signal picked up effectively.

V. Conclusion

FFT methods of vibration signal is adopted in system design,at same time differential temperature measurement methods is added into system to judge synthetically. The high capability DSP completes signal processing. This system can commendably satisfy the requirement for real-time processing. It monitors the signal of vibrations and temperatures with combining locomotive monitor and ground analysis. The earlier diagnosis and alarm for locomotive bearings fault can be given in order to assure locomotive running safely.

REFERENCES

[1] Wang Dezhi,The diagnosis and maintain of rolling bearing[M],Beijing: China Railway Publishing House, 1994,

[2] Shi Huafeng,Yin Guohua,etc,Fault diagnosis of locomotive bearing[J],Electric Drive For Locomotive, 2004,（2）: 40~43,

[3] Mei Hongbin,The libration monitoring and diagnosis of rolling bearing[M],Beijing：China Machine Press,1996,

[4] Mei Hongbin,The fault diagnosis for rolling bearings using envelope analysis,Bearing,1993 ,

（8）:30~34,

[5] Feng Gengbin,The libration diagnosis technology of the locomotive fault[M],Beijing: China Railway Publishing House,1994.

[6] Jiang Simi. The hardware exploiture of TMS320LF240x DSP. Beijing: China Machine Press, 2003.

[7] Qing Yuan Science and Technology. The application design of TMS320LF240XDS. Beijing: China Machine Press, 2003.

译文：

基于DSP技术为机车轴承设计故障诊断监控系统

摘要

滚动轴承是机车运行组件的关键部件之一,因为它直接关系到机车的性能和安全。在本文章中,监控系统为机车轴承基于DSP TMS320LF2407A的设计。这个系统使用振动分析方法来诊断滚动轴承的故障。它是在全面的共振解调和快速傅立叶变换技术基础上,采用”相关的方法”来处理FFT的结果。它有效的提高了轴承故障监控系统的反应特性,灵敏度,辨别和测量精度,它可以预测火车头运行中的故障和监测瞬态故障。

关键词: 共振解调技术；数字信号处理器；相关方法

1引言

列车有较高的安全需求是因为它的速度在不断提高。轴承故障是造成多样的交通事故和影响铁路安全的主要因素之一。目前,铁路系统通常采用轴承温度探测器来监察机车轴承的状况。理论分析和大量的实践证明,轴承温度探测器可以在一定程度上防止意外发生,但大部分的轴承故障对温度是不敏感的。当轴承的温度超过范围系统将发出警报,但不幸的是这时候轴承损伤已经发生,甚至是事故已发生。因此,为了更早期更准确的找到故障, 必须采用更先进的监测系统。大部分的轴承故障对振动信号非常的敏感。故障可能会导致轴承的振动增加。经分析和处理结果表明与监测轴承温度相比振动信号比温度的手段有更多的优势。

2系统的组成和工作过程

根据需要,监视器的轴承故障监测系统为机车轴承配置了两套侦测系统:itineration检测和固定的检测。 Itineration检测是用在正常情况条件下,

而固定检测用在轴承故障的连续检测。这个系统采用特殊复合传感器在同一时间收集轴承的振动和温度信号。经过数据处理,将获得相应的故障水平和上升了的温度。在这个系统中设计数据采集单元。报警信息通过接口会传送至所有的车厢,使工作人员可以及时的处理,与此同时,故障数据和列车的相关信息如目前的位置和速度将通过全球定位系统转交给派遣中心,派遣中心将采用相应的措施.该系统方框图如图1。

3为监控系统设计的关键技术

3.1频谱分析

在正常情况下,滚动轴承的各部分(内圈,外圈,滚动体,保持架)将保持相对稳定的工作状态。如果一些元素的表面(保持架除外)已有裂缝,而且这些裂缝在相邻表面也有,这时瞬时脉冲振动必须开启。

假设在轴承中滚动体的数量为Z ；滚动体的直径为d ；轴承的内圈和外圈的平均直径为D ；轴承的频率是0f 。假设内圈是固定的,外圈是回转的,振动频率可以

通过不同轴承零件的表面缺陷得到。

())(2101内圈f D d Z f +=

())(2101外圈f D d Z f -=

图1 系统方框图

())(]1[02

1滚动体f D d d D f -= 这些频率可以被称为内圈,外圈和滚动体的特色故障频密程度。

3.2共振解调技术

我们根据轴承零件的共振可以收集振动信号,并使用包络线探测器检测故障信号的包络线, 包络线探测器可以充分的分析故障的性质,这就是”共振解调技术”。一个零件的表面,如滚动轴承的内圈,外圈和滚动体极易在运作的过程中损坏(如点蚀,剥落,裂缝和划痕等)。如果一些轴承零件的表面在操作过程中有局部损伤和压力机故障斑点,必然会给操作带来影响。如果影响持续的时间很短,而且能源分歧的频率范围是广泛的,那么振动频率的能源与范围是小的。由于带宽的宽的脉冲,它理所应当的包含了固有高频率的振动,通过滚动轴承的内圈,外圈,滚动体和保持架的固有频率。共振解调信号被分离是通过带通滤波器的中心频率和它的固有频率相等实现的。然后包络线解调是通过有衰解振动波使用的软件或电路开展的,抹掉高频率衰解振动中的高频成分。我们只获得低频包络信号的故障特征的信息。包络信号的频谱分析是通过数字信号处理器来进行的,我们可以取得非常高的频率决议比例和很容易的找到相应的故障的频率,从而我们可以轴承故障的诊断。

共振解调技术,电动谐振器的共振频率的设计高于正常的振动频率和有限高次谐波的频率。因此,可以有效的抵制低频信号包括正常的振动信号。共振回应放大信号振幅的脉冲信号和它的振荡时间加长。因此,故障信号是扩大在时域上的信号。在包络检测和低通过滤器之后,低频共振解调信号高噪声信号比被输出。信号处理系统如图2所示。

图2 信号预处理

在轴承组件带来共振的影响下，形成的振荡不断衰减。通过研究每个衰减振荡，我们可以看到，其频率是轴承组件的固有频率，振幅衰减振荡是受到故障强度的影响。振幅包络信号的衰减振荡反映故障的大小，而且频密的重复程度取决于对故障的定位。系统有抗干扰低频振动，高信号与噪声的比例的表现。

3.3包络检测

轴承故障在轧制过程中经常回引起震动。不同的故障有不同的字频。该字频系统检测是包络信号的频率(这个频率被积累通过对轴承元件碰撞的故障)，而不是轴承的振动频率。当我们分析故障信号，共振频率(载波)必须除去包络解调。因为包络信号已充分包括了所有故障的信息，消除载波，将不会有任何不利于分析的影响。

4硬件和软件设计

硬件框图如图3所示

图3 轴承故障监测硬件框图

该电路包括两部分:振动信号预处理和轴承状态分析。信号预处理部分符合信号的扩增，转换和共振解调。轴承状态分析部分满足频谱分析信号，”相关法”处理，故障分级处理，轴承状况报告和与周边设备沟通等。

实现DSP主要有3种FFT算法:1、只包括加法和减法，没有运作的复数旋转因子。2、包括运作的复数旋转因子。3、比特位置反演的运作。通过这样的数据

处理，振动元件计算在DSP中的工作量明显减少。系统反应的时间可以得到改进。

模块化设计是通过软件的设计来实现的，软件的设计包括振动信号的集合和温度增量信号，A/D转换，数据预处理，FFT转换，计算功率谱，故障分级的判断，保存数据，显示数据和传送数据。任务调度是通过事件触发和时间触发这种方式进行的。用来消除干扰，”相关的意思是”FFT变换的结果进行处理，以保证故障回升信号有效。

5结语

振动处理的FFT方法是采用系统设计，在同一时间差温测量方法中加入综合评定的系统。高能力的DSP完成信号处理。这个系统可以满足实时处理的要求。它结合机车监控和地面分析监测振动的信号和温度。早期诊断和报警装置为机车轴承故障提供保障能保证机车运行安全。

参考资料

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附件1：外文资料翻译译文 64位PCI扩展 1.64位数据传送和64位寻址：独立的能力 PCI规范给出了允许64位总线主设备与64位目标实现64位数据传送的机理。在传送的开始，如果回应目标是一个64位或32位设备，64位总线设备会自动识别。如果它是64位设备，达到8个字节（一个4字）可以在每个数据段中传送。假定是一串0等待状态数据段。在33MHz总线速率上可以每秒264兆字节获取（8字节／传送＊33百万传送字／秒），在66MHz总线上可以528M字节／秒获取。如果回应目标是32位设备，总线主设备会自动识别并且在下部4位数据通道上（AD[31::00]）引导，所以数据指向或来自目标。 规范也定义了64位存储器寻址功能。此功能只用于寻址驻留在4GB地址边界以上的存储器目标。32位和64位总线主设备都可以实现64位寻址。此外，对64位寻址反映的存储器目标（驻留在4GB地址边界上）可以看作32位或64位目标来实现。 注意64位寻址和64位数据传送功能是两种特性，各自独立并且严格区分开来是非常重要的。一个设备可以支持一种、另一种、都支持或都不支持。 2.64位扩展信号 为了支持64位数据传送功能，PCI总线另有39个引脚。 ●REQ64#被64位总线主设备有效表明它想执行64位数据传送操作。REQ64#与FRAME#信号具有相同的时序和间隔。REQ64#信号必须由系统主板上的上拉电阻来支持。当32位总线主设备进行传送时，REQ64#不能又漂移。 ●ACK64#被目标有效以回应被主设备有效的REQ64#（如果目标支持64位数据传送），ACK64#与DEVSEL#具有相同的时序和间隔（但是直到REQ64#被主设备有效，ACK64#才可被有效）。像REQ64#一样，ACK64#信号线也必须由系统主板上的上拉电阻来支持。当32位设备是传送目标时，ACK64#不能漂移。 ●AD[64::32]包含上部4位地址／数据通道。 ●C/BE#[7::4]包含高4位命令/字节使能信号。 ●PAR64是为上部4个AD通道和上部4位C/BE信号线提供偶校验的奇偶校验位。 以下是几小结详细讨论64位数据传送和寻址功能。 3.在32位插入式连接器上的64位卡

毕业设计外文翻译格式实例.

理工学院毕业设计(论文)外文资料翻译 专业：热能与动力工程 姓名：赵海潮 学号：09L0504133 外文出处：Applied Acoustics, 2010(71):701~707 附件： 1.外文资料翻译译文；2.外文原文。

附件1：外文资料翻译译文 基于一维CFD模型下汽车排气消声器的实验研究与预测Takeshi Yasuda, Chaoqun Wua, Noritoshi Nakagawa, Kazuteru Nagamura 摘要目前，利用实验和数值分析法对商用汽车消声器在宽开口喉部加速状态下的排气噪声进行了研究。在加热工况下发动机转速从1000转/分钟加速到6000转/分钟需要30秒。假定其排气消声器的瞬时声学特性符合一维计算流体力学模型。为了验证模拟仿真的结果，我们在符合日本工业标准（JIS D 1616）的消声室内测量了排气消声器的瞬态声学特性，结果发现在二阶发动机转速频率下仿真结果和实验结果非常吻合。但在发动机高阶转速下（从5000到6000转每分钟的四阶转速，从4200到6000转每分钟的六阶转速这样的高转速范围内），计算结果和实验结果出现了较大差异。根据结果分析，差异的产生是由于在模拟仿真中忽略了流动噪声的影响。为了满足市场需求，研究者在一维计算流体力学模型的基础上提出了一个具有可靠准确度的简化模型，相对标准化模型而言该模型能节省超过90％的执行时间。 关键字消声器排气噪声优化设计瞬态声学性能 1 引言 汽车排气消声器广泛用于减小汽车发动机及汽车其他主要部位产生的噪声。一般而言，消声器的设计应该满足以下两个条件：（1）能够衰减高频噪声，这是消声器的最基本要求。排气消声器应该有特定的消声频率范围，尤其是低频率范围，因为我们都知道大部分的噪声被限制在发动机的转动频率和它的前几阶范围内。（2）最小背压，背压代表施加在发动机排气消声器上额外的静压力。最小背压应该保持在最低限度内，因为大的背压会降低容积效率和提高耗油量。对消声器而言，这两个重要的设计要求往往是互相冲突的。对于给定的消声器，利用实验的方法，根据距离尾管500毫米且与尾管轴向成45°处声压等级相近的排气噪声来评估其噪声衰减性能，利用压力传感器可以很容易地检测背压。 近几十年来，在预测排气噪声方面广泛应用的方法有：传递矩阵法、有限元法、边界元法和计算流体力学法。其中最常用的方法是传递矩阵法（也叫四端网络法）。该方

(机械设计理论)中英文对照 Machine design theory

机械设计理论 The machine design theory The machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question. Carries on each kind of machine design work to be usually called designs the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.