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The purpose of this paper is to study the failures spread in complex power grids, and what topology of power grids is best for preventing or reducing blackouts.

Based on the study of cascading failure models of complex power networks, an extended dynamical cascading failure model is proposed. Based on this model, two representatives of the complex power grids, the small‐world network and the scale‐free network, were simulated for line cascading failure. The power loss caused by cascading failures and the spreading speed of cascading failure are discussed.

Power loss caused by cascading failures in the small‐world network is much larger than that in the scale‐free network, and the speed of cascading failure propagation in the small‐world network is much faster than that in the scale‐free network.

The establishment of the dynamical cascading failure model considering other protection devices needs further study.

The results of this study can be beneficial in system planning and upgrading.

An extended dynamical cascading failure model is proposed and cascading failures in different topology of power grid are discussed.

Disasters of catastrophic scope and scale have occurred more frequently in recent years. Governmental and non-governmental response management has struggled, and affected communities have severely suffered during extreme events. Colossal damage and loss of lives have been inflicted, and the recovery efforts require extended periods of time. In post hoc analyses, actionable information has been found a critical resource requiring resilient information infrastructures (RIIs) that do not break down even under extreme duress. RIIs encompass both tangible and less tangible (for example, social) elements. The purpose of this paper is to pave the way for empirical research on the subject and to conceptually develop a framework for the analysis of information infrastructures and their resiliency, when impacted by catastrophic incidents (also known as extreme events).

The authors review the literatures of disaster research and related fields. They synthesize the literatures from the information perspective and develop a framework of RII.

The synthesis revealed that extreme event-ready RIIs have to be redundant and resourceful both in terms of social, organizational, and knowledge assets as well as in the information and communication technologies. RIIs combine tangible and non-tangible elements, whose interplay is so far incompletely understood.

Roles and criticality of RIIs under the impact of an extreme event need to be studied empirically.

The study holds the promise to be of great potential utility for responders and recovery managers as well as affected communities in preparedness, response, recovery, and mitigation efforts as timely and actionable information is still the scarcest and most sought resource during a catastrophic incident.

Disaster research so far has mostly focused on the technical, organizational, social, and socio-psychological effects of disasters. The authors are adding the information perspective as a unique and distinctive contribution to extreme event research, which connects the tangible elements of information infrastructures with its not so tangible elements, captures their interplay, and analyzes their role and criticality for the resiliency of the information infrastructures when under extreme duress.

Power outages which may be triggered, for example, by natural hazards and system failures are a common phenomenon, associated with large impacts on society including the healthcare sector. Minimising adverse impacts effectively requires an analysis of possible impacts and the identification of measures aiming at reducing vulnerability and increasing resilience.

To systematically identify impacts as well as preparation, mitigation and recovery (PMR) measures, a moderated workshop with participants representing different healthcare sub‐sectors in Germany was conducted and complemented by semi‐structured interviews and a thorough analysis of literature. Impacts were determined for three scenarios of power outage duration, <8, 8‐24 and >24 hours.

Whereas hospitals are in general well prepared with respect to shorter outages, due to obligatory emergency power in Germany, outpatient medical care, nursing homes (NH) and, in particular, home‐care nursing are early affected. Failure of these sub‐sectors puts additional strains on hospitals. If outages last more than one day and are associated with failure of other critical infrastructures (CIs), especially water supply, hospitals may be severely affected. Effective preparation and mitigation measures identified based on a facility‐specific impact analysis, as well as good cooperation between actors, may reduce impacts.

The largely case‐study‐based literature is complemented by a systematic and extensive analysis of direct and indirect impacts on the main healthcare sub‐sectors in Germany, followed by an identification of specific PMR measures. As a novelty outage duration is explicitly accounted for. Also, interdependencies between the healthcare sub‐sectors as well as dependencies on other CI are considered.

Uninterruptible Power Supply (UPS) systems are typically designed to provide power to computers for five to thirty minutes after all utility company power has failed. In addition to providing blackout and brownout protection, many UPS systems also protect against spikes, surges, sags, and noise, and some also offer many of the features found in power distribution units (PDUs). The major components or subsystems of a typical UPS system are detailed, and a sample bid specification is appended. Three sidebars discuss UPSs and air conditioning, the maintenance bypass switch (MBS), and literature for further reading.

If you have ever been caught by a power blackout or brownout — caused by lightning, storm damage, or simply a blunder by a repairman — and have completely lost work which was keyboarded but not yet stored on disk, you know how frustrating and infuriating that experience can be. There is little comfort, at such a moment, in realizing that your work habits should really include more frequent disk storage commands. Nor does it help to reflect that memory resident routines are available which automatically store keyboarded material to disk at frequent intervals.

Following a power blackout, unstable or excessive voltages are common during the first few seconds when power is restored. The Power Pause surge suppressor is a new device that protects electronic equipment from such “after blackout” over‐voltages.

To operate with high efficiency and minimise the risks of power failures, power systems require careful monitoring. The availability of real-time data is crucial for assessing the performance of the grid and assisting operators in gauging the present security of the grid. Traditional supervisory control and data acquisition (SCADA)-based systems actually employed provides steady-state measurement values which are the calculation premise of State Estimation. More often, however, the power grid operates under dynamic state and SCADA measurements can lead to erroneous and inaccurate calculation results. The introduction of the phasor measurement unit (PMU) which provides real-time synchronised voltage and current phasors with very high accuracy is universally recognised as an important aspect of delivering a secure and sustainable power system. PMUs are a relatively new technology and because of their high procurement and installation costs, it is imperative to develop appropriate methodologies to determine the minimum number of PMUs as well as their strategic placements to guarantee full observability of a power system. Thus, the problem of the optimal PMU placement (OPP) is formulated as an optimisation problem subject to various constraints to minimise the number of PMUs while ensuring complete observability of the grid. In this chapter, integer linear programming (ILP), genetic algorithm (GA) and non-linear programming (NLP) constrained models of the OPP problem are presented. A new methodology is proposed to incorporate several constraints using the NLP. The optimisation methods have been written in Matlab software and verified on the standard Institute of Electrical and Electronics Engineers (IEEE) 14-bus test system to authenticate their effectiveness. This chapter targets United Nations Sustainable Development Goal 7.

You have just entered two pages of carefully‐composed material into your word processor when the lights in your office dim and the computer screen goes dark. A few minutes later, the lights come back on again and you restart your computer. As it grinds through its start‐up procedures you wonder whether it will behave normally or leave you with a serious repair problem. This time you are lucky and your normal applications are available. However, when you open your word processor and look at the file you were entering, you find that your last two pages are missing.

This paper proposes a method of probabilistic security analysis of power systems including protection system failures. Protection system failure is the main cause of cascading outages. A protection system reliability model including two major protection failure modes is adopted to demonstrate the effects of different protection failure modes on power system reliability. The mechanism and scheme of protection system have been analyzed for their contribution to cascading outages as well as system stability after a fault occurs. All contingencies and responses in the power system are depicted in their inherent stochastic manner. Therefore, all simulations in this paper contain the features of a real power system. Non‐sequential Monte Carlo simulation approach is used to implement the stochastic properties of component contingencies and protection system failures. The WSCC‐9 bus system is used as the security test system. The security index “probability of stability” is calculated to quantify the vulnerability of a power system under cascading outages.