【作者】 张博；

【导师】 童杏林；

【作者基本信息】 武汉理工大学 ， 信息与通信工程， 2022， 硕士

【摘要】 定位测速技术是高速列车牵引和运行控制系统中的核心技术之一,对保证列车行驶过程中的运营安全有着至关重要的作用,是构建可靠列车安全体系的关键。目前,磁浮列车定位测速技术多使用基于电类系统的相对定位和绝对定位两种方法,受外界电磁干扰和传输速率低等因素影响,测量精度有限,无法满足磁浮列车的定位测速要求。针对此,本论文利用光纤布拉格光栅(Fiber Bragg Grating,FBG)传感技术的优势,深入研究了一种基于弱光纤光栅的磁浮列车定位测速传感器。论文的主要内容概括如下:(1)在分析现有国内外高速磁浮列车定位测速技术优缺点的基础上,针对目前磁浮列车测速定位的需求,提出了一种基于交变磁场的磁浮列车高精度定位测速光纤光栅传感器的研究思路。结合光纤光栅传感和信号解调的原理,研究了基于光纤光栅阵列的磁浮列车定位测速传感机理,并提出一种基于波峰波谷计数的高精度定位测速方法。(2)基于弹性力学原理,分析了用于磁浮列车定位测速的敏感机理,设计了一种蛇形弹性敏感结构,与圆柱形感应磁铁组成磁感应FBG传感单元;利用有限元仿真软件分析了磁感应FBG应变传感器敏感单元的共振频率和响应灵敏度对传感器性能的影响,获得了磁感应FBG应变传感器响应频率、灵敏度与传感单元结构的关系,并通过实验验证了磁感应FBG传感器的可行性。(3)研究了车载激励磁铁模组阵列对轨道定位测速传感光缆的作用机理。通过理论分析和模拟仿真,结合海尔贝克阵列(Halbach Array)思想,提出了一种适用于本文定位测速方法的车载激励磁铁模组阵列的排布方式。利用软件建模仿真了车载激励磁铁模组阵列,仿真结果表明,此排列方式可有效增强外界磁场强度,并可实现列车的高精度定位需求。(4)将车载激励磁铁模组阵列与轨道光纤光栅传感光缆相结合,搭建了一种基于弱光纤光栅阵列的磁浮列车定位测速系统。通过现场磁浮列车运动模拟试验,验证了本文所提定位测速方法的正确性,以及磁感应FBG应变传感器的响应特性和灵敏度。实验结果表明,本系统目前可实现低速状态下列车2cm的定位精度,测量速度平均误差范围在±1%以内。更多还原

【Abstract】 Location and speed measurement technology is one of the core technologies of high-speed trains and other rail transit vehicles,which plays a vital role in ensuring the safety of train operation during running,and is the key to building a reliable train safety system.At present,maglev train positioning and speed measurement technology mostly use relative positioning and absolute positioning based on the electrical system.Due to the influence of external electromagnetic interference and low transmission rate,the measurement accuracy is limited,which cannot meet the requirements of maglev train positioning and speed measurement.Given this,this paper makes use of the advantages of Fiber Bragg Grating(FBG)sensing technology to deeply study a maglev train positioning and speed sensor based on weak Fiber Bragg Grating.The main content of the paper is summarized as follows:(1)Based on the analysis of the advantages and disadvantages of existing high-speed maglev train location and speed measurement technologies at home and abroad,aiming at the current demand of maglev train location and location,a research idea of high-precision maglev train location and speed measurement fiber grating array sensor based on the alternating magnetic field is proposed.Combined with the sensing and signal demodulation principle of fiber grating,the mechanism of magnetic levitation train positioning and speed sensor based on fiber grating array is studied,and a high precision positioning and speed measurement method based on wave peak and wave valley counting are proposed.(2)Based on the principle of elasticity,the sensitivity mechanism of maglev train positioning and speed measurement is analyzed,and a snake-like elastic sensitive structure is designed to form a magnetic induction FBG sensing unit with a cylindrical induction magnet.Finite element simulation software was used to analyze the effects of resonance frequency and response sensitivity of magnetic induction FBG strain sensor on sensor performance,and the relationship between response frequency and sensitivity of magnetic induction FBG strain sensor and sensor structure was obtained.(3)The mechanism of the vehicle excitation magnet module array on the track positioning speed sensor cable is studied.Through theoretical analysis and simulation,combined with the idea of the Halbach Array,a kind of arrangement mode of vehicle-mounted excitation magnet module Array which is suitable for the positioning and velocity measurement method in this paper is proposed.Simulation software is used to simulate the vehicle-mounted excitation magnet module array,and the simulation results show that this arrangement can effectively enhance the external magnetic field intensity,and can meet the requirements of high-precision train positioning.(4)A maglev train positioning and speed measurement system based on ultra-low reflectivity fiber grating is built by combining the vehicle-mounted excitation magnet module array and track fiber grating sensing cable.The accuracy of the proposed method and the response characteristics and sensitivity of the magnetic induction FBG strain sensor are verified by the field maglev train motion simulation test.Experimental results show that the system can achieve the positioning accuracy of 2cm at low speed,and the average error of measuring speed is controlled by ±1%.更多还原