Blackout

About: Blackout is a research topic. Over the lifetime, 2088 publications have been published within this topic receiving 30433 citations.

Loss of short term memory as a predictor of the alcoholic "blackout".

Abstract: MEMORY loss caused by alcohol is a common occurrence. Most alcoholics report “blackouts” (amnesia) in connexion with drinking, and many nonalcoholics sometimes have trouble remembering events that occurred while they were intoxicated1. The cause of this is unknown. Some psychiatrists believe blackouts to be a functional disturbance, related to guilt or anxiety. Others believe they reflect a toxic effect of alcohol on the brain. There are few data to support either concept. Blackouts usually occur erratically; comparable amounts of alcohol do not always produce memory loss, and it has not been possible to predict when an intoxicated person will suffer amnesia. During the amnesic interval, the person may function reasonably well and perform complicated acts, suggesting that the amnesia is retrograde2. To confirm this, however, memory must be observed systematically during drinking periods followed by amnesia, which heretofore has not been done.

North American blackout time series statistics and implications for blackout risk

Abstract: We use North American Electric Reliability Corporation historical data to give improved estimates of distributions of blackout size, time correlations, and waiting times for the Eastern and Western interconnections of the North American grid. We then explain and estimate the implications of the power law region (heavy tails) in the empirical distribution of blackout size in the historical data for the Western interconnection. Annual mean blackout size has high variability and the risk of large blackouts exceeds the risk of medium size blackouts. Ways to communicate blackout risk are discussed.

Blackout mitigation assessment in power transmission systems

Abstract: 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 dynamics behave as a complex dynamical system. Here, we investigate how these complex system dynamics impact the assessment and mitigation of blackout risk. The mitigation of failures in complex systems needs to be approached with care. The mitigation efforts can move the system to a new dynamic equilibrium while remaining near criticality and preserving the power tails. Thus, while the absolute frequency of disruptions of all sizes may be reduced, the underlying forces can still cause the relative frequency of large disruptions to small disruptions to remain the same. Moreover, in some cases, efforts to mitigate small disruptions can even increase the frequency of large disruptions. This occurs because the large and small disruptions are not independent but are strongly coupled by the dynamics.

Application of a Wide Area Backup Protection Expert System to Prevent Cascading Outages

Abstract: A strategy to prevent cascading outages in power systems is proposed in this paper. The strategy employs wide-area back-up protection and artificial intelligence techniques to minimize the impact of a fault on a network. There are two ways in which wide-area backup protection can prevent cascading trips leading to a wide spread blackout: 1) Precise location of a fault so that only the circuit breakers necessary to isolate the fault are tripped; and 2) Avoidance of unnecessary trips, due to hidden failure or overloading, by blocking the trip signals of conventional back-up protection relays. The limitations of conventional back-up protection are examined and methods of improvement are presented.

Impact of clustering microgrids on their stability and resilience during blackouts

Abstract: In this paper, the impact of clustering multiple microgrids during blackouts, on their stability and supply availability, will be investigated. Microgrids have the capability of satisfying their emergency loads during blackouts. However, distributed energy resources (DERs)-dominated microgrids are affected by the uncertainty of their input energy supply, e.g. impact of solar irradiance on photovoltaic (PV) output. Moreover, an individual islanded microgrid is prone to instability issues due to large sudden load/generation changes. In order to increase the supply security, and enhance system stability, we propose to use the existing distribution grid infrastructure, if applicable, during blackouts to form microgrid clusters. The paper discusses the required control hierarchy required to manage the microgrid clusters, and communicate with the Distribution Network Operator (DNO). A case study based on the 13-bus standard distribution feeder, and two microgrid models, is presented. Results show that microgrids clustering helps improve their performance and that the microgrid generator inertia has a direct impact on the stability of the microgrid cluster.