Blackout

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

Lessons Learned From a Regional System Blackout and Restoration in BC Hydro

Abstract: A BC Hydro regional system experienced a blackout after multiple 500 kV lines, sharing the same transmission corridor, were subjected to lightning strikes in the time span of about three minutes. These lines connect two large generating stations, regional loads, and five nonutility generators to the rest of the BC Hydro system. The protection scheme on the first line tripped three-phase and initiated autoreclose as designed. However immediately after three-phase opening, high magnitudes of low-frequency (about 9 Hz) currents appeared in the line shunt reactor, causing a protection trip, and aborting the autoreclose. Subsequent lightning strikes coupled with a pre-existing line outage disconnected both generating stations from each other as well as from the integrated system. The larger of two generating stations and almost all regional load formed an islanded subsystem, which eventually collapsed and blacked out. During the restoration of the subsystem, the system operator inadvertently picked up the entire regional system without load, causing steady-state resonant overvoltages higher than 145% and damaging a transmission customer. This paper shares lessons learned from forensic analysis of disturbances leading to regional blackout and describes the risk of unsafe overvoltages from near power frequency resonant condition during the restoration process.

Analysis of cascading failures under interactions between power grid and communication network

Abstract: The conventional research on cascading failures in the power system is only limited in the physical power grid,in which interactions between power grid and communication network are seldom considered.With IEEE 118-bus system and New England 39-bus system as examples,the model of interaction between power grid and its communication network in accord with the practical power system is presented based on the DC power flow model.The impact of various routing strategies on the cascading failures of power system is investigated by adjusting the responding parameters of communication network and the inter-similarity between coupled networks is discussed based on the complex network theory.Simulative results indicate that,with proper routing strategy of communication network,the probability of cascading failures of power system can be reduced and the optimal inter-similarity strategy between coupled networks of different power systems is same,which can be adopted to effectively decrease the probability of large-scale blackout.

Control and prediction for blackouts caused by frequency collapse in smart grids

Abstract: The electric power system is one of the cornerstones of modern society. One of its most serious malfunctions is the blackout, a catastrophic event that may disrupt a substantial portion of the system, playing havoc to human life and causing great economic losses. Thus, understanding the mechanisms leading to blackouts and creating a reliable and resilient power grid has been a major issue, attracting the attention of scientists, engineers, and stakeholders. In this paper, we study the blackout problem in power grids by considering a practical phase-oscillator model. This model allows one to simultaneously consider different types of power sources (e.g., traditional AC power plants and renewable power sources connected by DC/AC inverters) and different types of loads (e.g., consumers connected to distribution networks and consumers directly connected to power plants). We propose two new control strategies based on our model, one for traditional power grids and another one for smart grids. The control strategies show the efficient function of the fast-response energy storage systems in preventing and predicting blackouts in smart grids. This work provides innovative ideas which help us to build up a robuster and more economic smart power system.

Event-based remedial action scheme against super-component contingencies to avert frequency and voltage instabilities

Abstract: Frequency instability, voltage instability or a combination of both have been the cause of several power system breakdowns throughout the world in the recent decades. Occurrence of a super-component contingency (SCC) that refers to multiple and simultaneous outages of grid facilities like a power plant or substation may lead to blackout if no remedial action schemes (RAS) are implemented. This study proposes a new event-based RAS to overcome the frequency and voltage instabilities caused by SCCs through optimal load shedding. To do this, a new multi-objective framework is presented simultaneously optimising the competing objective functions of long-term voltage stability margin, steady-state frequency deviation, maximum transient frequency deviation and load shed amount. A modified system frequency response model is also proposed for frequency stability assessment. Multi-objective decision making (MODM) is performed using a combination of analytical hierarchy process, modified augmented e-constraint method and technique for order preference by similarity to ideal solution. The effectiveness of both the proposed model and MODM solution approach is extensively illustrated on a simulated model of Iran's power system in 2012.