基于中点弦测法的中低速磁浮轨道不平顺研究  

Research on Medium and Low Speed Maglev Track Irregularity Based on Mid-chord Offset Method

作　　者：李梦雪 李苗 张敏[1] 马卫华[1] 李铁 张文跃 罗世辉[1] LI Mengxue;LI Miao;ZHANG Min;MA Weihua;LI Tie;ZHANG Wenyue;LUO Shihui(State Key Laboratory of Traction Power,Southwest Jiaotong University,Chengdu 610031,China;CRRC Dalian Co.,Ltd.,Dalian 116022,China;Institute of Maglev Systems,CRRC Zhuzhou Locomotive Co.,Ltd.,Zhuzhou 412001,China)

机构地区：[1]西南交通大学牵引动力国家重点实验室,成都610031 [2]中车大连机车车辆有限公司,大连116022 [3]中车株洲电力机车有限公司磁浮系统研究所,湖南株洲412001

出　　处：《铁道标准设计》2023年第9期49-55,共7页Railway Standard Design

基　　金：国家自然科学基金项目(51875483)。

摘　　要：中低速磁浮常用10 m弦测值作为评价轨道几何不平顺的标准,但弦测法的幅频特性存在畸变,这种畸变现象在短波范围内更加严重,导致10 m弦测值会丢失很多短波信号,因此,10 m弦测值通常不能作为实际轨道不平顺应用于工程实践中。针对此问题,采用数值模拟方法对中点弦测法进行模拟,通过对比弦测值时频域的误差,验证“以小推大”算法的准确性,同时建立两种“以小推大”的逆推算法,以得到小弦长的弦测值,扩大弦测值对短波不平顺的有效检测范围,并采用“逆滤波”法对弦测值进行轨道不平顺的反演。研究结果表明:两种“以小推大”逆推算法都可以很好地推得小弦长的弦测值,并且可推得的最小弦长为2倍步长,因此,为扩大短波的测量范围,应尽量缩小采样步长;模型A由于边界条件的引入,总体误差较模型B稍大,同时会出现一些离群点,功率谱密度会出现阶跃信号,绝对误差在0.025 mm以内;模型B可以达到较高的精度,具有很好的传递特性,绝对误差可以控制在0.0015 mm以内;实测长沙磁浮快线F轨10 m弦测值用两种模型均可以很好地反演0.5~100 m波长范围的轨距不平顺。The 10m chord versine is commonly used as the standard to evaluate track irregularity in medium and low speed maglev(MLSM).However,the amplitude frequency of the mid-chord offset method suffers distortion,which is more serious in the short waveform range,and the 10m chord versine will lose a lot of short waveform signals.Therefore,10m chord versine cannot be used in engineering practice as the true track irregularity.To solve this problem,the method of numerical simulation is used to simulate the process mid-chord offset method.By comparing the errors of 10m chord versine in time domain and frequency domain,the exactness of the“deduced from small to large”algorithm is verified,and two inverse algorithms of“deduced from small to large”are established to obtain the chord versine of small chord length,expand the effective detection range of short waveform irregularity,and the method of“inverse filtering”is used to inverse the short waveform irregularity.The results show that the two inverse algorithms of“deduced from small to large”can well deduce the chord versine of small chord length,and the minimum chord length that can be deduced is twice the step length.Therefore,in order to expand the Compared with model B,model A has a larger error due to the addition of boundary conditions,some outliers appear,step signals appear in the power spectral density,and the absolute error is within 0.025 mm.Model B has high accuracy and good transfer characteristics,and the absolute error can be controlled within 0.0015 mm.The field measurement of 10m chord versine of F-shaped track of Changsha Maglev Express Line shows that the track irregularities in the wavelength range of 0.5~100 m can be effectively inverted with both models.

关 键 词：中低速磁浮列车 轨道不平顺 中点弦测法 逆滤波 数值模拟 

分 类 号：U237[交通运输工程—道路与铁道工程] U213.2