Study On Contol Methods For Railway Station Signal Systems Based On Optical Fiber Technology

A railway signal system is the core component of railway operation. This system has great impact on how the railway operates. A railway signal system is a very complicated control system. The classical signal control system has low efficiency, and a relative long reaction time. Therefore, the classical signal control system can not meet the needs of the rapid development of railway transportation. One of the most important problem is the transmission the railway signal control information.Because the present railway control is with a rapid increase of information, such as device status information, control information, feedback information, and so on, the higher and higher speed of these information transmission is required, and the existing cable line can’t meet the requirements, which limits the development of railway signal control. This thesis fries to find a way to improve the efficiency, of the railway signal system by combining the traditional signal theory and communication technology of optical fiber technology of the network.This thesis involves the railway signal control method based on the traditional signal theory. The optical fiber technology is used for transmission between the core part in the system and the peripheral equipment, and some improvements of the optical fiber transmission are made. The main research contents include the following:(1) Because of the deficiency of the traditional signal transmission system, according to the characteristics of the optical fiber and railway signal theory, the signal optical fiber links are designed to meet the requirements of modern railway signal system.The proposed method overcomes the shortcomings of the traditional railway signal transmission methods, such as using the copper cable, low transmission efficiency, waste of resources and so on.(2) The railway signal system is simplified according to function into four layers: operation expression layer, interlock processing layer, executive drive layer, and outdoor terminal device layer. The detailed description of the function of each layer and the process are given. The executive drive layer and the outdoor terminal device layer are connected by fiber optic cable to improve efficiency. A specific method to the control core and a control terminal connected by fiber optic cable is proposed, and necessary measures are taken to ensure safety and reliable connections.(3) A flow chat of the signal system control is compiled. The flow chart is which is necessary for the use of computers with the help of the computer control theory, not only the control of the modular is realized, but also controlling equipments miniaturization is reached by electronic integration technology. Finally, Petri nets simulation for the flow chart is conducted; Petri nets can check the structure of the flow chart, for boundedness, activeness and the rationality of the process is verified.Finally, the summary of the thesis is given, followed by the perspective of future study.