Topology Estimation in Bulk Power Grids: Guarantees on Exact Recovery
Topology Estimation in Bulk Power Grids: Guarantees on Exact Recovery
复制标题
大容量电网的拓扑估计：精确恢复的保证
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
M. Salapaka
中科院分区：
文献类型：
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作者：
Deepjyoti Deka;Saurav Talukdar;M. Chertkov;M. Salapaka
电网的拓扑结构影响着其在电力市场中的动态运行和结算。实时拓扑识别可以在线路故障等紧急情况下实现更快的控制行动。本文讨论了一种利用从电网节点采集的电压测量来估计大电网(包括环网和径向分布)拓扑的图形化模型框架。给出了线性潮流模型中节点电压概率分布的图解模型，该模型包含了真实电网中的附加边和运行边。我们提出的估计算法首先学习图形模型，然后使用阈值或邻域计数方案来提取操作边缘。对于不含三节点环的网格拓扑(两条母线不共享公共邻居)，我们证明了从理论上保证了操作拓扑的精确提取。这包括大多数具有放射状拓扑的配电网。对于包含长度为3的圈的网格，我们给出了保证精确重建算法存在的充分条件。特别是，对于单位长度阻抗恒定且注入协方差均匀的电网，这一观察结果导致了母线地理位置的条件。在测试用例仿真中验证了算法的性能。
The topology of a power grid affects its dynamic operation and settlement in the electricity market. Real-time topology identification can enable faster control action following an emergency scenario like failure of a line. This article discusses a graphical model framework for topology estimation in bulk power grids (both loopy transmission and radial distribution) using measurements of voltage collected from the grid nodes. The graphical model for the probability distribution of nodal voltages in linear power flow models is shown to include additional edges along with the operational edges in the true grid. Our proposed estimation algorithms first learn the graphical model and subsequently extract the operational edges using either thresholding or a neighborhood counting scheme. For grid topologies containing no three-node cycles (two buses do not share a common neighbor), we prove that an exact extraction of the operational topology is theoretically guaranteed. This includes a majority of distribution grids that have radial topologies. For grids that include cycles of length three, we provide sufficient conditions that ensure existence of algorithms for exact reconstruction. In particular, for grids with constant impedance per unit length and uniform injection covariances, this observation leads to conditions on geographical placement of the buses. The performance of algorithms is demonstrated in test case simulations.