【作者】 许重府；

【导师】 李方敏；

【作者基本信息】 武汉理工大学 ， 通信与信息系统， 2007， 硕士

【摘要】 电力载波通信是以现有的电力电缆为载体实现数据交换的一种通信方式。随着网络通信技术的发展，这种由于不需要铺设通信专线，可有效降低系统的运行成本的通信技术开始在工业自动控制领域获得应用。铁路道岔及其转换设备是铁路线路中至关重要的设施又是轨道中的薄弱环节。道岔的动作由一般由液压转辙机来驱动。液压转辙的可靠动作对提高铁路运输效率和保证行车安全起着至关重要的作用。为防止转辙机故障当前普遍采用人工定期检查的方式，存在很大的不足。随着铁路向电气化和高速化发展，铁道部为确保行车安全，对铁路电务设备的检测与维修提出了更高的要求。针对现有铁路道岔液压转辙机油压检测方法存在的不足，设计了一种基于电力载波扩频通信的铁路道岔转辙机液压检测系统，实现对了铁路液压转辙机健康状况的实时在线监测，主要研究内容如下：(1)对电力线路的信道传输特性进行深入的研究并分析了常用的载波通信技术，通过比较最终选择抗干扰能力强的扩频通信技术作为系统的实现方案。(2)用集成电力载波CDMA扩频通信模块的单片机PL3201和自行设计的滤波放大器及其它辅助外围电路，构造出低压电力线载波通信的硬件电路系统。考虑到系统硬件规模的可扩展性，系统的数据集中部分采用子母板结构设计。(3)根据系统的实际情况定制了高效的载波通信协议，并针对系统通信过程中存在的误码问题提出数据的分段校验机制，大大降低了错误重传的次数，有效提高了系统在恶劣环境中的通信效率。(4)进行了现场装配和调试，进一步认识系统所存在的不足并做了相应的改进。最后提出了下一步的工作意见。更多还原

【Abstract】 Power line carrier communication is a kind of communication which takes the existing power line as the media for data exchange. It can reduce the cost of the system by saving the expenses on setting up a special line. With the development of network communication technology, it has been wildly used in automatic control field.The rail switch and converse equipment are very important, but unfortunately it is a weak link in railway. The movement of the rail switch is driven by hydraulic switch machine, it has great effect on the railway transport efficiency and traffic safety. In order to avoid accidents, workers have to check the hydraulic switch machine constantly to make sure that if it is working well or not. The railway is electrify and high-speed now, so ministry of railways has proposed an even higher demand on examination and repair to ensure driving safety.To improve existing methods that measure hydraulic pressure of switch machine, in this paper we design a kind of switch machine monitoring system which based on power line carrier communication. It can implement online and real-time monitoring on railway hydraulic switch machine. The following aspects are discussed in detail.(1) Transmission characteristic of power line circuit channel is studied and the commonly used communication technologies are analyzed. The spread spectrum communication technology is adopted in the realization scheme of this system.(2) The hardware circuitry system of low voltage electric power line carrier communication is make up with PL3201 and filter apmlifier and others auxiliary periphery circuit. Considering the expansibility of hardware system, the framework of mainboard and sub-board is used in part of data centralize system.(3) The efficiency communication protocol is desinged according to the actual situation of the system, and the partition mechanism of data verification is used to settle the bit error problem in the process of communication. It greatly reduces the times of re-transmission and effectively enhances the communicating efficiency of system in worst environment.(4) The assembling and debugging have been done on the spot, the disadvantages of the system has been found farther, and relative improvement has been finished. Finally, the advice of next work is provided.更多还原