配电网环境复杂,配电网同步相量测量装置(distribution network synchronous phasor measurement unit, D-PMU)容易受到干扰而产生坏数据,进一步影响基于测量数据的应用效果。为了提高D-PMU数据质量,提出一种不依赖系统拓扑的基于密度...配电网环境复杂,配电网同步相量测量装置(distribution network synchronous phasor measurement unit, D-PMU)容易受到干扰而产生坏数据,进一步影响基于测量数据的应用效果。为了提高D-PMU数据质量,提出一种不依赖系统拓扑的基于密度的噪场应用空间聚类(density-based spatial clustering of applications with noise, DBSCAN)的配电网同步测量坏数据检测方法。首先利用基于密度的聚类算法DBSCAN进行异常数据检测。通过轮廓系数和邓恩指数对DBSCAN的聚类结果进行综合评价。利用麻雀搜索算法实现自适应参数调整,解决检测时需要预先处理训练、标记数据的问题。在此基础上,将时间序列聚类的K-Medoids算法和动态时间规整算法相结合,通过衡量不同时间序列之间的相似性,解决了D-PMU在电气联系较弱时对扰动数据与坏数据的区分问题,增强了数据处理的准确性与噪声环境下的稳健性。仿真和实际数据的测试结果表明,所提方法能有效区分真实扰动数据并准确识别D-PMU坏数据。展开更多
Damage alarming and safety evaluation using long-term monitoring data is an area of significant research activity for long-span bridges. In order to extend the research in this field, the damage alarming technique for...Damage alarming and safety evaluation using long-term monitoring data is an area of significant research activity for long-span bridges. In order to extend the research in this field, the damage alarming technique for bridge expansion joints based on long-term monitoring data was developed. The effects of environmental factors on the expansion joint displacement were analyzed. Multiple linear regression models were obtained to describe the correlation between displacements and the dominant environmental factors. The damage alarming index was defined based on the multiple regression models. At last, the X-bar control chart was utilized to detect the abnormal change of the displacements. Analysis results reveal that temperature and traffic condition are the dominant environmental factors to influence the displacement. When the confidence level of X-bar control chart is set to be 0.003, the false-positive indications of damage can be avoided. The damage sensitivity analysis shows that the proper X-bar control chart can detect 0.1 cm damage-induced change of the expansion joint displacement. It is reasonably believed that the proposed technique is robust against false-positive indication of damage and suitable to alarm the possible future damage of the expansion joints.展开更多
文摘配电网环境复杂,配电网同步相量测量装置(distribution network synchronous phasor measurement unit, D-PMU)容易受到干扰而产生坏数据,进一步影响基于测量数据的应用效果。为了提高D-PMU数据质量,提出一种不依赖系统拓扑的基于密度的噪场应用空间聚类(density-based spatial clustering of applications with noise, DBSCAN)的配电网同步测量坏数据检测方法。首先利用基于密度的聚类算法DBSCAN进行异常数据检测。通过轮廓系数和邓恩指数对DBSCAN的聚类结果进行综合评价。利用麻雀搜索算法实现自适应参数调整,解决检测时需要预先处理训练、标记数据的问题。在此基础上,将时间序列聚类的K-Medoids算法和动态时间规整算法相结合,通过衡量不同时间序列之间的相似性,解决了D-PMU在电气联系较弱时对扰动数据与坏数据的区分问题,增强了数据处理的准确性与噪声环境下的稳健性。仿真和实际数据的测试结果表明,所提方法能有效区分真实扰动数据并准确识别D-PMU坏数据。
基金Project(2009BAG15B03) supported by the National Science and Technology Ministry of ChinaProjects(51178100, 51078080) supported by the National Natural Science Foundation of China+1 种基金Project(BK2011141) supported by the Natural Science Foundation of Jiangsu Province, ChinaProject(12KB02) supported by the Open Fund of the Key Laboratory for Safety Control of Bridge Engineering(Changsha University of Science and Technology), Ministry of Education, China
文摘Damage alarming and safety evaluation using long-term monitoring data is an area of significant research activity for long-span bridges. In order to extend the research in this field, the damage alarming technique for bridge expansion joints based on long-term monitoring data was developed. The effects of environmental factors on the expansion joint displacement were analyzed. Multiple linear regression models were obtained to describe the correlation between displacements and the dominant environmental factors. The damage alarming index was defined based on the multiple regression models. At last, the X-bar control chart was utilized to detect the abnormal change of the displacements. Analysis results reveal that temperature and traffic condition are the dominant environmental factors to influence the displacement. When the confidence level of X-bar control chart is set to be 0.003, the false-positive indications of damage can be avoided. The damage sensitivity analysis shows that the proper X-bar control chart can detect 0.1 cm damage-induced change of the expansion joint displacement. It is reasonably believed that the proposed technique is robust against false-positive indication of damage and suitable to alarm the possible future damage of the expansion joints.
