This work investigates the data quality issue for synchrophasor applications, and pays particular attention to synchronization signal loss and synchrophasor data loss events. First, the historical synchronization sign...This work investigates the data quality issue for synchrophasor applications, and pays particular attention to synchronization signal loss and synchrophasor data loss events. First, the historical synchronization signal loss events are analyzed and the potential reasons and solutions are discussed. Then, the scenario of a small amount of synchrophasor data loss is studied and a Lagrange interpolating polynomial method is used to adaptively estimate the incomplete and missing data. The performance of proposed method is demonstrated with simulation results.Specifically, the proposed method considers the trade-off between the estimation accuracy and the hardware cost,and could be efficiently employed in reality.展开更多
Time synchronization is one of the base techniques in wireless sensor networks(WSNs).This paper proposes a novel time synchronization protocol which is a robust consensusbased algorithm in the existence of transmissio...Time synchronization is one of the base techniques in wireless sensor networks(WSNs).This paper proposes a novel time synchronization protocol which is a robust consensusbased algorithm in the existence of transmission delay and packet loss.It compensates for transmission delay and packet loss firstly,and then,estimates clock skew and clock offset in two steps.Simulation and experiment results show that the proposed protocol can keep synchronization error below 2μs in the grid network of 10 nodes or the random network of 90 nodes.Moreover,the synchronization accuracy in the proposed protocol can keep constant when the WSN works up to a month.展开更多
研究能量长期有效的时间同步协议是成功部署生命力强的无线传感器网络的一项关键策略,对此,提出一种低能耗的多跳自适应时间同步算法MATS(Multi-Hop Adaptive Time Synchronization),该算法设计了一套灵活的机制来调整同步模式、全网重...研究能量长期有效的时间同步协议是成功部署生命力强的无线传感器网络的一项关键策略,对此,提出一种低能耗的多跳自适应时间同步算法MATS(Multi-Hop Adaptive Time Synchronization),该算法设计了一套灵活的机制来调整同步模式、全网重同步周期以及每对节点同步时的信标数,并且利用最大似然估计原理同时对节点的时钟偏移和频率偏移进行估计,达到用最小的能量损耗完成长期的、全网的时间同步的目的,最后通过数学分析和仿真的方法对所提出的改进算法进行了验证。展开更多
基金supported in part by the U.S.National Science Foundation(U.S.NSF)through the U.S.NSF/Department of Energy(DOE)Engineering Research Center Program under Award EEC-1041877 for CURENT
文摘This work investigates the data quality issue for synchrophasor applications, and pays particular attention to synchronization signal loss and synchrophasor data loss events. First, the historical synchronization signal loss events are analyzed and the potential reasons and solutions are discussed. Then, the scenario of a small amount of synchrophasor data loss is studied and a Lagrange interpolating polynomial method is used to adaptively estimate the incomplete and missing data. The performance of proposed method is demonstrated with simulation results.Specifically, the proposed method considers the trade-off between the estimation accuracy and the hardware cost,and could be efficiently employed in reality.
文摘Time synchronization is one of the base techniques in wireless sensor networks(WSNs).This paper proposes a novel time synchronization protocol which is a robust consensusbased algorithm in the existence of transmission delay and packet loss.It compensates for transmission delay and packet loss firstly,and then,estimates clock skew and clock offset in two steps.Simulation and experiment results show that the proposed protocol can keep synchronization error below 2μs in the grid network of 10 nodes or the random network of 90 nodes.Moreover,the synchronization accuracy in the proposed protocol can keep constant when the WSN works up to a month.
文摘研究能量长期有效的时间同步协议是成功部署生命力强的无线传感器网络的一项关键策略,对此,提出一种低能耗的多跳自适应时间同步算法MATS(Multi-Hop Adaptive Time Synchronization),该算法设计了一套灵活的机制来调整同步模式、全网重同步周期以及每对节点同步时的信标数,并且利用最大似然估计原理同时对节点的时钟偏移和频率偏移进行估计,达到用最小的能量损耗完成长期的、全网的时间同步的目的,最后通过数学分析和仿真的方法对所提出的改进算法进行了验证。