Phasor Measurement Units (PMU), due to their capability for providing highly precise and time-synchronized measurements of synchrophasors, have now become indispensable in wide area monitoring of power-grid systems. Successful and reliable delivery of synchrophasor packets from the PMUs to the Phasor Data Concentrators (PDCs) and beyond, requires a backbone communication network that is robust and resilient to failures. These networks are vulnerable to a range of failures that include cyber-attacks, system or device level outages and link failures. In this paper, we present a framework to evaluate the resilience of a PMU network in the context of link failures. We model the PMU network as a connected graph and link failures as edges being removed from the graph. Our approach, inspired by model checking methods, involves exhaustively checking the reachability of PMU nodes to PDC nodes, for all possible combinations of link failures, given an expected number of links fail simultaneously. Using the IEEE 14-bus system, we illustrate the construction of the graph model and the solution design. Finally, a comparative evaluation on how adding redundant links to the network improves the Power System Observability, is performed on the IEEE 118 bus-system.
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Probabilistic Network Observability of a Hybrid Power System with Communication Irregularities
This paper explores power system network
observability while taking into account realistic communication
network behavior. The overall information is obtained by
combining SCADA- and phasor measurement unit-derived data,
where time stamping (based on Global Positioning System or an
equivalent local clock) for all measurements is assumed. Based on
simulations performed in communication Network Simulator 2,
empirical cumulative distribution functions can be associated
with transfer times of measurement packets, which will reflect
communication parameters and irregularities. This is further
used to form an algorithm which maximizes the number of
successful network observability checks, and thus the number of
possible state estimations, in a certain time period. Application is
demonstrated on the IEEE 14-bus test power system example.
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- NSF-PAR ID:
- 10163323
- Date Published:
- Journal Name:
- 2019 North American Power symposium
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/NAPS46351.2019.8999986
