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Time synchronized measurements of voltage magnitudes or phasors are increasingly common in electrical networks. Voltage measurement statistics are informative of the underlying network structure or topology making them useful for grid monitoring. However, this connection is poorly understood and many proposed voltage analytics are purely heuristic. We use graph theory to establish sound theoretical connections between voltage measurements and the structure of the underlying network. Our results are important for many applications, from topology estimation to missing data recovery. Based on this new theory, we discuss existing analytics, transforming them from heuristic to theoretically justified approaches, and introduce new analytics. We clarify all assumptions made, to indicate when analytics may fail or perform poorly. Our work enables voltage measurement streams to be transformed into physically meaningful, intuitive, visualizable, actionable information through simple algorithms. 

The push to automate and digitize the electric grid has led to widespread installation of Phasor Measurement Units (PMUs) for improved real-time wide-area system monitoring and control. Nevertheless, transforming large volumes of highresolution PMU measurements into actionable insights remains challenging. A central challenge is creating flexible and scalable online anomaly detection in PMU data streams. PMU data can hold multiple types of anomalies arising in the physical system or the cyber system (measurements and communication networks). Increasing the grid situational awareness for noisy measurement data and Bad Data (BD) anomalies has become more and more significant. Number of machine learning, data analytics and physics based algorithms have been developed for anomaly detection, but need to be validated with realistic synchophasor data. Access to field data is very challenging due to confidentiality and security reasons. This paper presents a method for generating realistic synchrophasor data for the given synthetic network as well as event and bad data detection and classification algorithms. The developed algorithms include Bayesian and change-point techniques to identify anomalies, a statistical approach for event localization and multi-step clustering approach for event classification. Developed algorithms have been validated with satisfactory results for multiple examples of power system events including faults and load/generator/capacitor variations/switching for an IEEE test system. Set of synchrophasor data will be available publicly for other researchers.