高速磁浮轨道导向不平顺检测系统的研究

Guidance irregularity detection system of track for high-speed maglev transit

高速磁浮列车是利用电磁力实现车辆与轨道无接触高速运行的一种新型交通工具,车辆的导向和制动性能受到轨道导向不平顺的影响。为了保证高速磁浮车辆运行的安全性、稳定性和舒适性,设计一种结构简化、低成本和搭载式的磁浮轨道导向不平顺检测系统。该系统基于惯性基准法原理实现检测,由加速度计、测距传感器、数据记录仪和里程检测模块组成,并未使用陀螺仪和倾角仪测量载体的姿态角变化。分析了车辆姿态变化对导向不平顺检测误差的影响,因未修正姿态导致的检测误差绝对值在直线段轨道达到0.4 mm,而在曲线段轨道超过了3 mm。为了降低缺乏姿态观测所致误差,提出一种设计线型辅助的策略用以部分替代倾角仪功能,即以列车所在位置轨道的横坡角和纵坡角分别近似替代载体的侧滚角和俯仰角低频分量,并用于补偿加速度积分中的重力和离心力分量,仿真表明该方法可将曲线段轨道的检测误差降低至0.6 mm。此外,结合磁浮轨道刚度大、变形小以及分段铺设的特点,利用分段直线拟合方法对不平顺检测结果进行平滑处理,从而进一步降低缺乏姿态观测的影响,保证系统具有足够的检测精度。通过小车检测试验,结果表明所设计系统及数据处理方法可实现±0.5 mm之内的检测误差。

High-speed maglev train is a new type of transportation which uses electromagnetic force to realize the non-contact high-speed running between vehicle and track.The guidance and braking performance of the vehicle is affected by the track guidance irregularity.In order to ensure the safety,stability and comfort of high-speed maglev vehicles,a simple,low-cost,on-board maglev track guidance irregularity detection system was designed.Based on the principle of inertial reference method,the system was composed of accelerometer,displacement meter,data recorder and mileage detection module.Gyroscope and inclinometer were not used to measure the attitude of the carrier.This paper analyzed the influence of vehicle attitude on the detection error of guidance irregularity.The absolute value of the detection error caused by uncorrected attitude reached 0.4 mm in the straight track and more than 3 mm in the curved track.In order to reduce the error caused by the lack of attitude observation,a strategy of designing linear auxiliary was proposed to partially replace the inclination meter function.The horizontal gradient and longitudinal gradient of the track,where the train was located,were approximately used to replace the low-frequency components of the carrier's roll angle and pitch angle,respectively.The gravity and centrifugal force components in the acceleration integration were compensated.Simulation results show that this method can reduce the detection error of curve track to 0.6 mm.In addition,combined with the characteristics of high rigidity,small deformation and subsection laying of the maglev track,the subsection straight line fitting method is used to smooth the irregularity detection results,so as to further reduce the impact of the lack of attitude observation and ensure that the system has sufficient detection accuracy.The test results show that the designed system and data processing method can achieve the detection error within±0.5 mm.