3,376 research outputs found
Vulnerability analysis of satellite-based synchronized smart grids monitoring systems
The large-scale deployment of wide-area monitoring systems could play a strategic role in supporting the evolution of traditional power systems toward smarter and self-healing grids. The correct operation of these synchronized monitoring systems requires a common and accurate timing reference usually provided by a satellite-based global positioning system. Although these satellites signals provide timing accuracy that easily exceeds the needs of the power industry, they are extremely vulnerable to radio frequency interference. Consequently, a comprehensive analysis aimed at identifying their potential vulnerabilities is of paramount importance for correct and safe wide-area monitoring system operation. Armed with such a vision, this article presents and discusses the results of an experimental analysis aimed at characterizing the vulnerability of global positioning system based wide-area monitoring systems to external interferences. The article outlines the potential strategies that could be adopted to protect global positioning system receivers from external cyber-attacks and proposes decentralized defense strategies based on self-organizing sensor networks aimed at assuring correct time synchronization in the presence of external attacks
Quantum correlations and synchronization measures
The phenomenon of spontaneous synchronization is universal and only recently
advances have been made in the quantum domain. Being synchronization a kind of
temporal correlation among systems, it is interesting to understand its
connection with other measures of quantum correlations. We review here what is
known in the field, putting emphasis on measures and indicators of
synchronization which have been proposed in the literature, and comparing their
validity for different dynamical systems, highlighting when they give similar
insights and when they seem to fail.Comment: book chapter, 18 pages, 7 figures, Fanchini F., Soares Pinto D.,
Adesso G. (eds) Lectures on General Quantum Correlations and their
Applications. Quantum Science and Technology. Springer (2017
Dynamical heterogeneity and universality of power-grids
While weak, tuned asymmetry can improve, strong heterogeneity destroys
synchronization in the electric power system. We study the level of
heterogeneity, by comparing large high voltage (HV) power-grids of Europe and
North America. We provide an analysis of power capacities and loads of various
energy sources from the databases and found heavy tailed distributions with
similar characteristics. Graph topological measures, community structures also
exhibit strong similarities, while the cable admittance distributions can be
well fitted with the same power-laws (PL), related to the length distributions.
The community detection analysis shows the level of synchronization in
different domains of the European HV power grids, by solving a set of swing
equations. We provide numerical evidence for frustrated synchronization and
Chimera states and point out the relation of topology and level of
synchronization in the subsystems. We also provide empirical data analysis of
the frequency heterogeneities within the Hungarian HV network and find
q-Gaussian distributions related to super-statistics of time-lagged
fluctuations, which agree well with former results on the Nordic Grid.Comment: 15 pages, 15 figure
Inherent Synchronization in Electric Power Systems with High Levels of Inverter-based Generation
The synchronized operation of power generators is the foundation of electric
power system stability and key to the prevention of undesired power outages and
blackouts. Here, we derive the condition that guarantees synchronization in
electric power systems with high levels of inverter-based generation when
subjected to small perturbations, and perform a parametric sensitivity to
understand synchronization with varied types of generators. Contrary to the
popular belief that achieving a stable synchronized state is tied chiefly to
system inertia, our results instead highlight the critical role of generator
damping in achieving this pivotal state. Additionally, we report the
feasibility of operating interconnected electric grids with a 100% power
contribution from renewable generation technologies with assured system
synchronization. The findings of this paper can set the basis for the
development of advanced control architectures and grid optimization methods and
has the potential to further pave the path towards the decarbonization of the
electric power sector
Power-Law Distributions of Dynamic Cascade Failures in Power-Grid Models
Power-law distributed cascade failures are well known in power-grid systems.
Understanding this phenomena has been done by various DC threshold models,
self-tuned at their critical point. Here we attempt to describe it using an AC
threshold model, with a second-order Kuramoto type equation of motion of the
power-flow. We have focused on the exploration of network heterogeneity
effects, starting from homogeneous 2D lattices to the US power-grid, possessing
identical nodes and links, to a realistic electric power-grid obtained from the
Hungarian electrical database. The last one exhibits node dependent parameters,
topologically marginally on the verge of robust networks. We show that too weak
quenched heterogeneity, coming solely from the probabilistic self-frequencies
of nodes (2D lattice) is not sufficient to find power-law distributed cascades.
On the other hand too strong heterogeneity destroys the synchronization of the
system. We found agreement with the empirically observed power-law failure size
distributions on the US grid, as well as on the Hungarian networks near the
synchronization transition point. We have also investigated the consequence of
replacing the usual Gaussian self-frequencies to exponential distributed ones,
describing renewable energy sources. We found a drop in the steady state
synchronization averages, but the cascade size distribution both for the US and
Hungarian systems remained insensitive and have kept the universal tails,
characterized by the exponent . We have also investigated the
effect of an instantaneous feedback mechanism in case of the Hungarian
power-grid.Comment: Extended version with minor changes, accepted in Entropy 22 pages, 13
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