CAJ | 학술논문

为了研究在途检测车辆运行的动态稳定性问题，在分析机车车辆动力学响应特点的基础上，基于响应信号的非平稳特征提出一种动态检测车辆运动稳定性的时变阻尼比的新方法。该方法的核心是对横向振动加速进行改进经验模式分解，得到信号的基本模式分量。分别对信号的基本模式分量进行归一化希尔伯特变换得到模式分量对应的瞬时频率和瞬时幅值，应用瞬时幅值和瞬时频率计算该模式下信号的时变阻尼比。由时变阻尼比的正负来判断车辆的运行稳定性，正的时变阻尼比表明车辆运行稳定，零或负时频阻尼比表明车辆运行失稳，负的时频阻尼比的绝对值大小表明了车辆失稳的严重程度。通过仿真算例和线路实测信号对该方法进行理论和试验验证，结果表明该方法能够从响应信号中准确、有效地捕捉系统稳定性的动态时变特征，为机车车辆运动稳定性的在途监测提供有效方法。
위료연구재도검측차량운행적동태은정성문제，재분석궤차차량동역학향응특점적기출상，기우향응신호적비평은특정제출일충동태검측차량운동은정성적시변조니비적신방법。해방법적핵심시대횡향진동가속진행개진경험모식분해，득도신호적기본모식분량。분별대신호적기본모식분량진행귀일화희이백특변환득도모식분량대응적순시빈솔화순시폭치，응용순시폭치화순시빈솔계산해모식하신호적시변조니비。유시변조니비적정부래판단차량적운행은정성，정적시변조니비표명차량운행은정，령혹부시빈조니비표명차량운행실은，부적시빈조니비적절대치대소표명료차량실은적엄중정도。통과방진산례화선로실측신호대해방법진행이론화시험험증，결과표명해방법능구종향응신호중준학、유효지포착계통은정성적동태시변특정，위궤차차량운동은정성적재도감측제공유효방법。
In order to dynamically detect vehicle motion stability during operation, as a new method of detecting vehicle motion stability, the time-varying damping ratio, is presented on the basis of the analysis of the dynamic response feature and the non-stationary characteristics of the response signals. The lateral vibration accelerations are decomposed by the IEMD(improved empirical mode decomposition) into a finite and often small number of IMF(intrinsic mode functions). The instantaneous frequency and the instantaneous amplitude of the intrinsic mode components are drawn through normalized Hilbert transform, respectively. The time-varying damping ratios under different intrinsic modes are computed by applying instantaneous amplitude and instantaneous frequency to judge the running stability of the vehicle. The zero or negative damping ratio indicates that the vehicle is unstable, the positive damping ratio shows that the vehicle keeps stable, the absolute value of the negative ratio means the severity of vehicle instability. Through the theoretical and experimental verification applying simulation and the measured signals, the results show the method can accurately and efficiently dynamically capture the time-varying characteristics of the system stability, with a powerful method for transit monitoring of vehicle running stability.