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

1、原文：Design of Fault Diagnosis Monitor System for the LocomotiveBearings Based on DSP TechnologyAbstractThe 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 sys

2、tem 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 r

3、esult 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 demodul

4、ation technology; digital signal processor; related methodsI. IntroductionThe 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 u

5、ses 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 tempera

6、ture of the bearing is beyond the range and the system gives an alarm, the worse damage of the bearing has occurred, and even theincident 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 sensit

7、ive 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 processBased on the need, the

8、 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 adopt

9、s 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 al

10、l 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 sys

11、tem block diagram is in Fig. 1. III. The key technology of the design for the monitoring systemA. The spectrum analysis means for diagnosing bearing faultUnder normal circumstances, all parts of the rolling bearing (inner circle, outer circle, roller, holding frame will retain the stable relative mo

12、vement 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

13、 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 defe

14、cts 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.f 1=Z (1+d D f 02(inner circlef 1=Z (1-d D f 02(outer circlef 1=D d 1-(d D f 0(roller2 B. Resonance demodulation technologyWe can co

15、llect 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 ou

16、ter 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 o

17、peration, 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 i

18、nspiring 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

19、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 pr

20、ocessor, 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

21、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

22、 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, f

23、orm 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 envelopesignal of the attenuation osc

24、illation 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 detectionA bearing with fault in the course of rolling will bring regular

25、 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 sign

26、al, 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 designThe hardware block diagram of the mo

27、nitor 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 spect

28、rum analysis of the signal, "correlation method" processing, fault grading processing, thebearings 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 with

29、out 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 resp

30、onse 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

31、 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 u

32、p effectively. V. ConclusionFFT 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

33、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.REFERENCES1 Wang Dezhi,The diagnosis and maintain

34、 of rolling bearingM,Beijing: China Railway Publishing House, 1994,2 Shi Huafeng,Yin Guohua,etc,Fault diagnosis of locomotive bearingJ,Electric Drive For Locomotive, 2004,（2）: 4043,3 Mei Hongbin,The libration monitoring and diagnosis of rolling bearingM,Beijing：China Machine Press,1996,4 Mei Hongbin

35、,The fault diagnosis for rolling bearings using envelope analysis,Bearing,1993 ,（8）:3034,5 Feng Gengbin,The libration diagnosis technology of the locomotive faultM,Beijing: China Railway Publishing House,1994.6 Jiang Simi. The hardware exploiture of TMS320LF240x DSP. Beijing: China Machine Press, 20

36、03.7 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

37、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

38、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

39、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。 图1 系统方框图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f 0。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。f 1=Z (1+d D f 02(内圈 f 1=Z (1-d D f 02(外圈f

40、1=D d 1-(d D f 0(滚动体2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