一种基于时频图的列车运行状态在线监测系统及方法

发布时间：2018-05-19 12:45

本文选题：分布式光纤振动传感系统 + 列车运行状态监测　；参考：《电子科技大学》2017年硕士论文

【摘要】：目前,国内外每年都有发生因脱轨导致的交通事故,严重地威胁着人们的生命财产安全,给经济的增长带来负面影响。随着列车的提速和承载的加大,列车运行状态的监测日趋重要。本文提出了基于相位敏感光时域反射仪的分布式光纤振动传感技术的列车运行状态在线监测方法,该方法利用分布式光纤采集因列车行驶而产生的轨道振动信号,对信号作短时傅里叶变换得到时频图,从时频图中挖掘轨道振动信号特征,从而实现对列车运行状态的安全监测。本文的主要研究内容如下:首先,分析了分布式光纤传感技术的技术类型和传感原理,并对分布式光纤振动传感原理进行详细分析,并阐述了将其用于列车运行状态在线监测系统的监测原理。其次,对列车轨道信号进行特征分析,重点分析了轨道信号的频域特征,即时频图。接着,分析了NLM滤波(Nonlocal Means Filtering)的原理及其对时频图预处理的效果。再次,根据需求,设计了基于(37)-OTDR的分布式光纤振动传感技术的列车运行状态在线监测系统,并详细说明了系统结构、硬件实现和轨道振动信号处理算法,包括信号的获取、分析、处理。最后,阐述了本监测系统的性能指标,并对NLM滤波的效果进行对比评价;之后,对本系统进行现场测试,并对结果进行分析,证明了该系统的可行性,接着对本系统和信号处理算法进行了推广。
[Abstract]:At present, traffic accidents caused by derailment occur every year at home and abroad, which seriously threaten the safety of people's life and property and bring negative impact to economic growth. With the increase of train speed and load, the monitoring of train running status is becoming more and more important. In this paper, a distributed optical fiber vibration sensing technique based on phase sensitive optical time domain reflectometer is proposed for on-line monitoring of train running state. This method uses distributed optical fiber to collect track vibration signals caused by train running. The time-frequency map is obtained by short-time Fourier transform, and the track vibration signal features are mined from the time-frequency map to realize the safety monitoring of train running state. The main contents of this paper are as follows: firstly, the technology types and sensing principles of distributed optical fiber sensing technology are analyzed, and the distributed optical fiber vibration sensing principle is analyzed in detail. The monitoring principle of the on-line monitoring system for train running condition is expounded. Secondly, the characteristic analysis of train track signal is carried out, and the frequency domain feature and instant frequency chart of track signal are analyzed. Then, the principle of NLM filter Nonlocal Means filtering and its effect on pretreatment of time-frequency graph are analyzed. Thirdly, according to the requirements, a distributed optical fiber vibration sensing system based on distributed optical fiber vibration sensor technology is designed, and the system structure, hardware implementation and track vibration signal processing algorithm, including signal acquisition, are described in detail. Analysis, treatment. Finally, the performance index of the monitoring system is expounded, and the effect of NLM filtering is compared and evaluated. Then, the field test of the system is carried out, and the results are analyzed, which proves the feasibility of the system. Then the system and signal processing algorithm are generalized.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP274;U284.48

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