The Application Research Of Fiber Bragg Grating In Train Monitoring System

Railway transportation plays an important role in the national economic development. So it is of great significance to guarantee the safety of railway transportation through real-time monitoring of the train. But the train’s runtime environment is very harsh, such as intense EMI and corrosiveness. With poor resistance of EMI and short transmission distance, the recently used current sensor, which is unstable and easy to corrode, is hard to form large-scale sensor networks and to be used in real-time monitoring of the train. Unlike current sensor, FBG sensor has long-term stability and high accuracy. Besides, we can realize multipoint distribution monitoring by multiplexing technology. So in order to fill gaps of current sensor and provide effective way, it is better to apply FBG sensing technology to real-time monitoring of the train.Combining above characteristics of FBG sensor with the runtime environment of high speed train, this research aims at the special requirements of high speed train, and studies deployment of FBG sensor monitoring system, which is suitable for the train. In this case, the advantages of FBG sensor can be made full use, and the reliability of the safe operation of the train can be improved significantly.The paper mainly includes3parts:(1) On the basis of FBG mode coupling theory and the calculation method of spectral characteristic, this paper establishes spectral characteristic figure of FBG through MATLAB simulation. Based on FBG spectral characteristic and packaging technique, this paper comes up with the properly package structure for temperature sensor, strain sensor and acceleration sensor according to the real runtime environment of the train. Also, this paper analyzes the characteristic and structure of FBG sensor.(2) This paper analyzes structure characteristic, multiplexing capacity and power efficiency of FBG sensing network multiplexing technology, including WDM, TDM, SDM, and hybrid multiplexing. Based on these characteristics of different multiplexing and real requirements of the train, this paper establishes FBG sensor network layout of WDM+optical switch structure. Also, it assigns wavelength for FBG sensor base on broadband source.(3) This paper designs a remote software platform based on ENLIGHT software command set of MOI interrogator and TCP/IP module of LABVIEW. It realizes the multi-user and multiple master control room monitor. Based on the remote software platform, simulated and actual experiments of the train are implemented by using FBG sensor under current conditions.