基于DSP的移频轨道电路参数在线检测方法研究

【作者】 耿浩利；

【导师】 王安；

【作者基本信息】 西北工业大学 ， 控制科学与工程， 2007， 硕士

【摘要】 铁路在国民经济的发展中起到了很重要的作用。随着铁路技术的发展，列车在运行速度及运载能力上有了很大的提高。为了保证行车安全，确保铁路运输的安全畅通，对列车在运行时的安全防护提出了很高的要求。确保列车正常运行的技术手段有很多，其中轨道电路是保障列车正常运行的重要手段之一。 我国轨道电路的制式主要是移频轨道电路，包括国产18信息移频轨道电路和引进法国UM71型并加以国产化的ZPW—2000型移频轨道电路。二者均以频率作为参数，实现信息的传递。由于轨道电路所处的环境非常恶劣，需要定期检测轨道电路的相关运行参数，判断轨道电路及信号设备是否处于最佳工作状态，可以及时消除隐患，确保列车的行车安全。 基于传统检测方法的轨道信号检测方式存在诸多弊端。在总结和分析国内外相关研究工作的基础上，通过对移频信号的频谱特点进行分析，得出国产18信息移频轨道信号频谱具有双峰，双峰频率的平均值就是移频信号的载频中心频率，而ZPW—2000移频轨道电路的频谱为单峰，峰值频率即为信号的载频中心频率，频谱上谱线的间距即为低频调制频率。给出了利用快速傅立叶变换(FFT)进行频谱分析的方法，实现了对移频轨道电路信号的载频和低频调制频率的检测。为了保证检测的精度要求，设计中通过理论推导计算，采用了低于正常采样频率的采样频率对信号进行FFT变换。给出了不同的频率范围下，具体的采样频率计算公式。论文中利用Matlab和信号发生器及数字示波器对利用FFT实现移频轨道电路参数检测的方法进行了仿真验证，并进行相应的计算。验证结果表明理论分析与实际的计算结果能够保持一致，证明所采用方法的正确性。 在检测方法的基础上，以DSP处理器TMS320F2812为核心，设计相关电路，选择合适的芯片，建立实际的硬件平台，利用CCS开发工具实现对DSP的软件编程，实现了液晶的显示功能和对模拟信号的采样及显示。更多还原

【Abstract】 The railway transportation plays an important role in the development of the national economic. As the the development of the railway technology, the speed and the carry ability of the railway greatly improved. In order to assure the safety of the railway traveling, a higher requirement has been rased for the realtime security of the train. There are several technic skills to make everything run smoothly. The railway circuit is one of the most critical methods to insure safety transportation.The frequency-shift railway circuit is the main railway circuit in our country, including 18-information frequency-shift auto-blocking railway circuit made in China and UM-71 jointless railway circuit made in France which localized ZPW-2000. Both of them use the frequency as the transport parameter. Usually, the rail is used as the signal channel to establish the relationship between the signal equipment and the running train. As the serious environment where the railway circuit equipped, some testing is needed periodically to evaluate whether the railway circuit and the signal equipment are in a good state.The detecting systems based on the traditional methods are facing serious challenge. At the basis of the former research work and the analysis of the frequency-shift signal. As to the carrier frequency, the spectrum of the 18-information frequency-shift railway signal has two peaks, the carrier frequency is the average of the two peak frequency. The ZPW-2000 jointless track signal has only one peak, the carrier frequency is the peak frequency. This paper gives fast Fourier transform to check the signal and proves correctness with some tools.The TMS320F2812 is used as the core processing unit based the test mothed. The related circuits are well designed. Hardware platform is established and realized the display and the A/D sample.更多还原