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Electric power transmission systems are a key infrastructure and blackouts of these systems have major direct and indirect consequences on the economy and national security. Analysis of North American Electrical Reliability Council blackout data suggests the existence of blackout size distributions with power tails. This is an indication that blackout(More)
We define a model for the evolution of a long series of electric power transmission system blackouts. The model describes opposing forces which have been conjectured to cause self-organized criticality in power system blackouts. There is a slow time scale representing the opposing forces of load growth and growth in system capacity and a fast time scale(More)
We introduce branching process models in discrete and continuous time for the exponentially increasing phase of cascading blackouts. Cumulative line trips from real blackout data have portions consistent with these branching process models. Some initial calculations identifying parameters and using a branching process model to estimate blackout(More)
We give an overview of a complex systems approach to large blackouts of electric power transmission systems caused by cascading failure. Instead of looking at the details of particular blackouts, we study the statistics and dynamics of series of blackouts with approximate global models. Blackout data from several countries suggest that the frequency of(More)
A model for blackouts in electric power transmission systems is implemented and studied in simple networks with a regular structure. The model describes load demand and network improvements evolving on a slow timescale as well as the fast dynamics of cascading overloads and outages. The model dynamics are demonstrated on the simple power system networks.(More)
algorithms time complexity ROM space special condition modulo adder size PI wg 4 > n2 no n*M PI wg 4 2 yes 2 " PI O(n) &n " , no M New algorithm 000~ nl O(n) no <M 1001 in the figure are the same. Each cell in the tree performs the findno algorithm. In the diagram, the RNS representation is used as input to the first level of cells in pair, i.e. is the(More)
We suggest a statistical estimator to quantify the propagation of cascading transmission line failures in large blackouts of electric power systems. We use a Galton-Watson branching process model of cascading failure and the standard Harris estimator of the mean propagation modified to work when the process saturates at a maximum number of components. If(More)
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We examine correlations in a time series of electric power system blackout sizes using scaled window variance analysis and R/S statistics. The data shows some evidence of long time correlations and has Hurst exponent near 0.7. Large blackouts tend to correlate with further large blackouts after a long time interval. Similar effects are also observed in many(More)
Thyristor controlled reactors are high power switching circuits used for static VAR control and the emerging technology of flexible ac transmission. The static VAR control circuit considered in the paper is a nonlinear periodically operated RLC circuit with a sinusoidal source and ideal thyristors with equidistant firing pulses. This paper describes new(More)