基于递归理论的泵站压力管道运行状态监测

Monitoring the Operating Condition of Pipeline of Pumping Stations Based on Recurrence Theory

针对不利因素导致的管道运行异常问题,提出一种基于递归理论的泵站管道运行状态监测方法。首先,通过振动传感器提取压力管道关键部位的实测信息,并将同一位置不同方向的数据信息进行融合,得到一组反映结构整体动力特性的综合数据;其次,利用伪近临法与互信息法分别选取相空间重构参数m和τ;最后,绘制并计算代表管道动力特性的递归图及递归量化指标。将该方法应用于景泰川工程二期七泵站管道运行监测,通过设置不同的运行工况进行验证,结果表明:机组开关瞬间与稳定运行工况下,管道结构振动信号的递归图呈现不同模式,递归量化指标-确定性、对角线平均长度L、递归率及递归熵也呈现明显差异,能有效区分管道振动状态。该方法为压力管道的无损动态监测提供了新思路。

Aiming at the abnormal operation of pipeline caused by unfavorable factors,anoperational monitoring method of pipeline based on Recurrence theory is proposed.First of all,the vibration sensor is used to extract the measured information of key parts of the pressure pipeline and fuse the data of different directionsat the same position to obtain a set of comprehensive data that reflect the overall dynamic characteristics of the structure.And then,embedding dimension(m)and time delay(τ),these two parameters of the phase space reconstruction,are selectedby using false nearest neighbor methodand mutual information method,respectively.Finally,the recurrence plot and recursive quantification indexes which represent the dynamic characteristics of pipeline are drawn and calculated.The method is applied to the operational monitoring of the second stageseventh pipeline of Jingtaichuan project,andit is verified by setting different operating conditions.The results show that the recurrence plots of the pipeline vibration signalspresentdifferent modes under the conditions of switching unit transient and stablely operating.The recursive quantification indexes and thedeterminism,the diagonal average length,the recurrence rate and the recurrence entropy also shows significant differences,whichcan effectively distinguish the pipeline vibration state.Therefore,the method provides a new idea for the non-destructive dynamic monitoring of pressure pipeline.