基于光纤感测技术的城市轨道交通钢轨状态实时监测方法

为了有效监测城市轨道交通钢轨实时状态,确保列车运行过程中轨道信号采集能力和交通运行安全,提出了基于光纤感测技术的城市轨道交通钢轨状态实时监测方法。通过光纤光栅传感器,对钢轨各个状态信号进行了连续采集,采用光栅解调仪全光谱扫描后,传送至监控模块接收状态信号。利用小波变换,对钢轨高频、低频时间和频率进行了细化处理。通过小波包分解转换后的信号,结合小波包能量谱,分析了该频带上的高频和低频信号。依据频带信号总能量的变化情况监测钢轨,并将监测后的数据存储至数据库,实现了城市轨道交通钢轨状态实时监测。测试结果表明,该方法的光学损耗低于 0.8% ,迟滞误差均低于 0.8% ,能够采集列车运行过程中的轨道的高频段和低频信号,有效分析异常能量变化位置。

Real Time Monitoring Method of Rail Status of Urban Rail Transit Based onOptical Fiber Sensing Technology

In order to effectively monitor the realtime status of urban rail transit and ensure the rail signal acquisition ability and traffic safety during train operation,a realtime monitoring method of rail status of urban rail transit based on optical fiber sensing technology is proposed.Through various fiber grating sensors,each status signal of rail is continuously collected,and after full spectrum scanning by grating demodulator,it is transmitted to the monitoring module to receive the status signal.The time and frequency of rail highfrequency and lowfrequency are refined by wavelet transform.The highfrequency and lowfrequency signals in this band are analyzed by the conversed signal of wavelet packet decomposition and wavelet packet energy spectrum.The rail is monitored according to the change of total energy of band signal,and the monitored data is stored in the database to realize the realtime monitoring of rail status of urban rail transit.The test results show that the optical loss of this method is less than 0.8%,and the hysteresis error is less than 0.8%.It can collect the highfrequency and lowfrequency signals of the rail during train operation,and effectively analyze the position of abnormal energy change.