Nowadays, the technology of renewable sources grid-connection and DC transmission has a rapid development. And phasor measurement units(PMUs) become more notable in power grids, due to the necessary of real time monit...Nowadays, the technology of renewable sources grid-connection and DC transmission has a rapid development. And phasor measurement units(PMUs) become more notable in power grids, due to the necessary of real time monitoring and close-loop control applications. However, the PMUs data quality issue affects applications based on PMUs a lot. This paper proposes a simple yet effective method for recovering PMU data. To simply the issue, two different scenarios of PMUs data loss are first defined. Then a key combination of preferred selection strategies is introduced. And the missing data is recovered by the function of spline interpolation. This method has been tested by artificial data and field data obtained from on-site PMUs. The results demonstrate that the proposed method recovers the missing PMU data quickly and accurately. And it is much better than other methods when missing data are massive and continuous. This paper also presents the interesting direction for future work.展开更多
The invention of Phasor Measurement Units(PMUs)produce synchronized phasor measurements with high resolution real time monitoring and control of power system in smart grids that make possible.PMUs are used in transmit...The invention of Phasor Measurement Units(PMUs)produce synchronized phasor measurements with high resolution real time monitoring and control of power system in smart grids that make possible.PMUs are used in transmitting data to Phasor Data Concentrators(PDC)placed in control centers for monitoring purpose.A primary concern of system operators in control centers is maintaining safe and efficient operation of the power grid.This can be achieved by continuous monitoring of the PMU data that contains both normal and abnormal data.The normal data indicates the normal behavior of the grid whereas the abnormal data indicates fault or abnormal conditions in power grid.As a result,detecting anomalies/abnormal conditions in the fast flowing PMU data that reflects the status of the power system is critical.A novel methodology for detecting and categorizing abnormalities in streaming PMU data is presented in this paper.The proposed method consists of three modules namely,offline Gaussian Mixture Model(GMM),online GMM for identifying anomalies and clustering ensemble model for classifying the anomalies.The significant features of the proposed method are detecting anomalies while taking into account of multivariate nature of the PMU dataset,adapting to concept drift in the flowing PMU data without retraining the existing model unnecessarily and classifying the anomalies.The proposed model is implemented in Python and the testing results prove that the proposed model is well suited for detection and classification of anomalies on the fly.展开更多
基于单一线路两端的监控与数据采集系统(supervisory control and data acquisition system,SCADA)和相量采集装置(phasor measurement unit,PMU)多时段量测信息,建立了5种独立线路的约束最小二乘参数估计模型,其中,量测方程分别由线路...基于单一线路两端的监控与数据采集系统(supervisory control and data acquisition system,SCADA)和相量采集装置(phasor measurement unit,PMU)多时段量测信息,建立了5种独立线路的约束最小二乘参数估计模型,其中,量测方程分别由线路两端有功、无功和电压幅值的SCADA量测、电流与电压相量的PMU量测以及线路两端电压相角差的PMU虚拟量测组合形成,约束方程为参数变量的上下限约束。采用Matlab的lsqnonlin优化函数求解参数估计问题,并基于多条典型线路的模拟量测信息仿真分析了所有模型的适用条件。结果表明,在负荷较重、线路较长条件下,利用所建含PMU量测的4种模型,都可以有效估计出线路的阻抗参数。展开更多
当前应用于状态估计的量测数据由广域测量系统(wide area measurement system,WAMS)和数据监控及采集系统(supervisory control and data acquisition,SCADA)采集,WAMS向量测量单元(phasor measurement unit,PMU)的优化配置问题成为研...当前应用于状态估计的量测数据由广域测量系统(wide area measurement system,WAMS)和数据监控及采集系统(supervisory control and data acquisition,SCADA)采集,WAMS向量测量单元(phasor measurement unit,PMU)的优化配置问题成为研究的重点。本文在分析WAMS/SCADA混合量测数据成分、时间断面、精度、刷新频率4个方面差异的基础上,实现了混合量测数据的有效兼容,提出了一种基于无迹卡尔曼滤波(unscented kalman filter,UKF)动态状态估计和离散粒子群优化(discrete particle swarm optimization,DPSO)算法的PMU优化配置方案。采用该方案下的混合量测数据进行UKF动态状态估计,很好地提高了状态估计精度。在IEEE39节点系统上模拟日负荷变化验证了该PMU配置方案的有效性。展开更多
根据来自监视控制与数据采集(supervisory control and data acquisition,SCADA)系统和相量测量单元(phasor measurement unit,PMU)的数据特点,提出了一种基于SCADA/PMU混合量测的广域动态实时状态估计方法,该方法充分利用了各节点间电...根据来自监视控制与数据采集(supervisory control and data acquisition,SCADA)系统和相量测量单元(phasor measurement unit,PMU)的数据特点,提出了一种基于SCADA/PMU混合量测的广域动态实时状态估计方法,该方法充分利用了各节点间电压变化的相互联系,通过SCADA系统提供的初始值和安装PMU的节点的电压量测可简单地获得其他未安装PMU节点的电压相量。该方法有效地解决了在PMU配置不足的情况下如何观测电网状态以及如何在动态过程下实时观测电网。最后,通过对新英格兰10机39节点系统的多种故障进行仿真,验证了该方法的有效性和准确性。展开更多
基金supported in part by National Natural Science Foundation of China(NSFC)(51627811,51707064)Project Supported by the National Key Research and Development Program of China(2017YFB090204)Project of State Grid Corporation of China(SGTYHT/16-JS-198)
文摘Nowadays, the technology of renewable sources grid-connection and DC transmission has a rapid development. And phasor measurement units(PMUs) become more notable in power grids, due to the necessary of real time monitoring and close-loop control applications. However, the PMUs data quality issue affects applications based on PMUs a lot. This paper proposes a simple yet effective method for recovering PMU data. To simply the issue, two different scenarios of PMUs data loss are first defined. Then a key combination of preferred selection strategies is introduced. And the missing data is recovered by the function of spline interpolation. This method has been tested by artificial data and field data obtained from on-site PMUs. The results demonstrate that the proposed method recovers the missing PMU data quickly and accurately. And it is much better than other methods when missing data are massive and continuous. This paper also presents the interesting direction for future work.
文摘The invention of Phasor Measurement Units(PMUs)produce synchronized phasor measurements with high resolution real time monitoring and control of power system in smart grids that make possible.PMUs are used in transmitting data to Phasor Data Concentrators(PDC)placed in control centers for monitoring purpose.A primary concern of system operators in control centers is maintaining safe and efficient operation of the power grid.This can be achieved by continuous monitoring of the PMU data that contains both normal and abnormal data.The normal data indicates the normal behavior of the grid whereas the abnormal data indicates fault or abnormal conditions in power grid.As a result,detecting anomalies/abnormal conditions in the fast flowing PMU data that reflects the status of the power system is critical.A novel methodology for detecting and categorizing abnormalities in streaming PMU data is presented in this paper.The proposed method consists of three modules namely,offline Gaussian Mixture Model(GMM),online GMM for identifying anomalies and clustering ensemble model for classifying the anomalies.The significant features of the proposed method are detecting anomalies while taking into account of multivariate nature of the PMU dataset,adapting to concept drift in the flowing PMU data without retraining the existing model unnecessarily and classifying the anomalies.The proposed model is implemented in Python and the testing results prove that the proposed model is well suited for detection and classification of anomalies on the fly.
文摘基于单一线路两端的监控与数据采集系统(supervisory control and data acquisition system,SCADA)和相量采集装置(phasor measurement unit,PMU)多时段量测信息,建立了5种独立线路的约束最小二乘参数估计模型,其中,量测方程分别由线路两端有功、无功和电压幅值的SCADA量测、电流与电压相量的PMU量测以及线路两端电压相角差的PMU虚拟量测组合形成,约束方程为参数变量的上下限约束。采用Matlab的lsqnonlin优化函数求解参数估计问题,并基于多条典型线路的模拟量测信息仿真分析了所有模型的适用条件。结果表明,在负荷较重、线路较长条件下,利用所建含PMU量测的4种模型,都可以有效估计出线路的阻抗参数。
文摘当前应用于状态估计的量测数据由广域测量系统(wide area measurement system,WAMS)和数据监控及采集系统(supervisory control and data acquisition,SCADA)采集,WAMS向量测量单元(phasor measurement unit,PMU)的优化配置问题成为研究的重点。本文在分析WAMS/SCADA混合量测数据成分、时间断面、精度、刷新频率4个方面差异的基础上,实现了混合量测数据的有效兼容,提出了一种基于无迹卡尔曼滤波(unscented kalman filter,UKF)动态状态估计和离散粒子群优化(discrete particle swarm optimization,DPSO)算法的PMU优化配置方案。采用该方案下的混合量测数据进行UKF动态状态估计,很好地提高了状态估计精度。在IEEE39节点系统上模拟日负荷变化验证了该PMU配置方案的有效性。
文摘根据来自监视控制与数据采集(supervisory control and data acquisition,SCADA)系统和相量测量单元(phasor measurement unit,PMU)的数据特点,提出了一种基于SCADA/PMU混合量测的广域动态实时状态估计方法,该方法充分利用了各节点间电压变化的相互联系,通过SCADA系统提供的初始值和安装PMU的节点的电压量测可简单地获得其他未安装PMU节点的电压相量。该方法有效地解决了在PMU配置不足的情况下如何观测电网状态以及如何在动态过程下实时观测电网。最后,通过对新英格兰10机39节点系统的多种故障进行仿真,验证了该方法的有效性和准确性。