适用于梯级泵站压力管道的传感器优化布置方法

为解决梯级泵站压力管道传感器优化布置问题,提出一种基于有效独立-总位移法的传感器优化布置方法。该方法针对有效独立法所选测点能量较小的缺陷,将测点的总位移以权重的方式加入传感器优化过程中,并保留有效独立法的优点,最终得到独立性较好且满足能量要求的测点。以景泰压力管道为例,运用该方法进行传感器优化布置,并与传统有效独立法比较,通过模态置信准则、Fisher信息矩阵值、最大奇异值比以及总位移等指标评价2种方法的优劣。结果表明,有效独立-总位移法得到的测点在满足独立性的前提下,增加了测点信息量,可观性更好。优化前后实测数据的比较分析,表明该方案对实际结构检测具有较好的适用性,是一种实用有效的传感器优化布置方法。

Sensor placement optimization method for pressure pipeline suitable for grading pumping station

Abstract: As the basic carrier of long-distance inter-basin water conveyance project of cascade, cascade pumping station is an important part of agricultural engineering and water conservancy projects, which plays an important role on solving the uneven space-time distribution of water resources. Safety monitoring research of cascade pumping station pressure pipe structure is a focus of current structural health monitoring and dynamic recognition research. But in practical engineering, safety monitoring of pressure pipeline structure is mostly based on experience of the sensor measurement points for decorate, which has a great deal of subjectivity and blindness. In order to solve the problem of pressure pipeline sensor optimization of cascade pumping station, an improved effective independence sensor placement optimization method based on total displacement is proposed. Effective independence method is about to obtain the best point to estimate the modal space independence by calculating the covariance matrix between the measuring points. Two candidate sensor location independence of measuring points may have the large contribution of modal vectors, but not have necessarily larger measuring point distribution in energy, which may lead to the lost of important structure information. What is more, the displacement and corresponding strain energy of structure damage are commonly large in practical engineering. Effective independence-total displacement method adds the total displacement of measuring points in the form of weighting sensor in the process of sensor placement optimization. The effective independence-total displacement method can retain the advantages of effective independence method, which overcomes the shortcomings of getting the points with less energy. The measuring points got by the effective independence-total displacement method can get good independence and satisfy the requirement of energy. Taking 3# pumping station 2# pipeline of second phase of Jingtai cascade pumping station as the research object, the effective independence method and effective independence-total displacement method were applied to achieve sensor placement optimization. Finally the optimal placement with different methods was gotten when the sensor number was 14. Comparing the effect of improved method with traditional effective independence, regarding modal confidence criterion, maximum singular value ratio, fisher information matrix and total displacement as evaluation index, total displacement criterion was proposed to ensure the final evaluation index of strain energy of the measured points in this paper. Study showed that effective independence-total displacement method could improve the strain energy and observability of the remaining measuring points, which could also retain the independence of each other. In addition, through the comparison of the measured data before and after optimization showed that the selected number and location of measuring points are reasonable. This improved method has good applicability to the practical structure monitoring, which shows that it is an effective and practical method for optimal sensor placement. The effective independence-total displacement method has achieved good results in solving the problem of sensor placement optimization of the cascade pumping station pressure pipeline, which can effectively avoid the problem of large strain energy measuring point information lost and ensure the independence between the measuring points. It is a kind of reliable sensor optimization method.