基于空间状态辨识理论的高速铁路车体垂向加速度预测模型

轨道不平顺是引起车辆振动的主要激励源。深入分析轨道高低不平顺与车体垂向加速度关联关系动态,掌握轨道结构传递特性,对科学评价车辆、轨道的服役状态及精准指导线路养护维修具有重要意义。基于系统辨识理论,以我国高速综合检测列车车载检测系统在一高速铁路上的实测轨道不平顺及车体垂向加速度样本数据为基础,通过平均周期图谱法计算检测数据功率谱密度及其相干函数,用状态空间方法构建长波轨道高低不平顺与车体垂向加速度之间的传递模型,并用关联模型传递函数及实测数据对所建模型进行验证。结果表明:模型预测的车体垂向加速度与相应实测数据有较强的线性相关性;利用合理阶数的状态空间模型,能够有效辨识长波轨道高低不平顺与车体垂向加速度之间的传递关系。

Prediction Model of High Speed Railway Car-body Vertical Acceleration Based on Space-state Identification Theory

Track irregularity is the main source of vehicle vibration.It is important to analyze the dynamic relationship between the track longitudinal irregularity and the vertical acceleration of the car-body and master the transmission characteristics of the track structure,so as to evaluate the service status of the vehicle/track scientifically and guide the track maintenance accurately.Based on the system identification theory and the sample data of track irregularity and vertical acceleration of car-body measured by the on-board inspection system of a high-speed comprehensive inspection train in a high-speed railway in China,the power spectral density and its correlation function of the inspection data were calculated by means of the average periodic spectrum method,and the transmission model between the long wave track longitudinal irregularity of and the vertical acceleration of car-body was constructed by the state-space method.The transfer function of the correlation model and the measured data were used to verify the model.The results show that the vertical acceleration predicted by the model has a strong linear correlation with the corresponding measured data,and the transfer relationship between the track longitudinal irregularity of the long wave and the vertical acceleration of the car-body can be effectively identified by using the state-space model of reasonable order.