Zeitschriftenartikel: „Power System Blackouts“

1

Haes Alhelou, Hassan, Mohamad Hamedani-Golshan, Takawira Njenda und Pierluigi Siano. „A Survey on Power System Blackout and Cascading Events: Research Motivations and Challenges“. Energies 12, Nr. 4 (20.02.2019): 682. http://dx.doi.org/10.3390/en12040682.

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Power systems are the most complex systems and have great importance in modern life. They have direct impacts on the modernization, economic, political and social aspects. To operate such systems in a stable mode, several control and protection techniques are required. However, modern systems are equipped with several protection schemes with the aim of avoiding the unpredicted events and power outages, power systems are still encountering emergency and mal-operation situations. The most severe emergencies put the whole or at least a part of the system in danger. If the emergency is not well managed, the power system is likely to have cascading failures that might lead to a blackout. Due to the consequences, many countries around the world have research and expert teams who work to avoid blackouts on their systems. In this paper, a comprehensive review on the major blackouts and cascading events that have occurred in the last decade are introduced. A particular focus is given on the US power system outages and their causes since it is one of the leading power producers in the world and it is also due to the ready availability of data for the past events. The paper also highlights the root causes of different blackouts around the globe. Furthermore, blackout and cascading analysis methods and the consequences of blackouts are surveyed. Moreover, the challenges in the existing protective schemes and research gaps in the topic of power system blackout and cascading events are marked out. Research directions and issues to be considered in future power system blackout studies are also proposed.

2

Hasanvand, Saeed, Hossein Fallahzadeh-Abarghouei und Esmaeil Mahboubi-Moghaddam. „Power system security improvement using an OPA model and IPSO algorithm“. SIMULATION 96, Nr. 3 (07.11.2019): 325–35. http://dx.doi.org/10.1177/0037549719886356.

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The growing demand for power generation makes power systems increasingly more complex to operate and less secure against outages, so the risk of extensive blackouts is growing and needs to be addressed. Cascading failures are the main reason for extensive blackouts, so to investigate this effect a new method including a standard blackout model, named ORNL-PSerc-Alaska (OPA), and static synchronous series compensator (SSSC) placement using an improved particle swarm optimization (IPSO) algorithm is proposed. This study provides two optimization approaches and presents optimal corrective actions. The results will help operators to implement corrective actions like optimal generation and load redispatching to return the system to a stable operating condition. The effectiveness of the proposed model is demonstrated using a realistic transmission network. Simulation results show a significant effect of SSSC on decreasing the risk of cascading failures and the ability of the proposed method to prevent blackout.

3

Yu, Qun, Na Cao, Qilin Liu, Yuqing Qu und Yumin Zhang. „Self-Organized Criticality and Trend Analysis in Time Series of Blackouts for the China Power Grid“. Mathematical Problems in Engineering 2020 (29.08.2020): 1–8. http://dx.doi.org/10.1155/2020/3075935.

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This paper proposes effective evidence on the correlation between trend and self-organized criticality (SOC) of the power outage sequence in China. Taking the data series of blackouts from 1981 to 2014 in the China power grid as the research object, the method of V/S is introduced into the analysis of the power system blackout sequence to demonstrate their prominent long-time correlations. It also verifies the probability distribution of load loss about blackout size in the China power grid has a tail feature, which shows that the time series of blackouts in the China power grid is consistent with SOC. Meanwhile, a kind of mathematical statistics analysis is presented to prove that there is a seasonal trend of blackouts, and the blackout frequency and blackout size have not decreased over time but have an upward trend in the China power grid, thereby indicating that blackout risk may be increasing with time. The last 34 years’ data samples of power failure accidents in the China power grid are used to test the proposed method, and the numerical results show that the proposed self-organized criticality and trend analysis method can pave the way for further exploration of the mechanism of power failure in the China power grid.

4

Brinkis, K., V. Kreslins und A. Mutule. „Operative and technological management of super-large united power grids: lessons of major world’s blackouts“. Latvian Journal of Physics and Technical Sciences 51, Nr. 1 (01.02.2014): 3–11. http://dx.doi.org/10.2478/lpts-2014-0001.

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ABSTRACT Power system (PS) blackouts still persist worldwide, evidencing that the existing protective structures need to be improved. The discussed requirements and criteria to be met for joint synchronous operation of large and super-large united PSs should be based on close co-ordination of operative and technological management of all PSs involved in order to ensure secure and stable electricity supply and minimise or avoid the threat of a total PS blackout. The authors analyse the July 2012 India blackout - the largest power outage in history, which affected over 620 million people, i.e. half of India’s population and spread across its 22 states. The analysis is of a general character, being applicable also to similar blackouts that have occurred in Europe and worldwide since 2003. The authors summarise and develop the main principles and methods of operative and technological management aimed at preventing total blackouts in large and super-large PSs.

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Al-Odienat, Abdullah I. „Power System Blackouts: Analysis and Simulation of August 9, 2004 Blackout in Jordan Power System“. Information Technology Journal 5, Nr. 6 (15.10.2006): 1078–82. http://dx.doi.org/10.3923/itj.2006.1078.1082.

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6

Faraji, Jamal, Masoud Babaei, Navid Bayati und Maryam A.Hejazi. „A Comparative Study between Traditional Backup Generator Systems and Renewable Energy Based Microgrids for Power Resilience Enhancement of a Local Clinic“. Electronics 8, Nr. 12 (05.12.2019): 1485. http://dx.doi.org/10.3390/electronics8121485.

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Extreme weather events lead to electrical network failures, damages, and long-lasting blackouts. Therefore, enhancement of the resiliency of electrical systems during emergency situations is essential. By using the concept of standby redundancy, this paper proposes two different energy systems for increasing load resiliency during a random blackout. The main contribution of this paper is the techno-economic and environmental comparison of two different resilient energy systems. The first energy system utilizes a typical traditional generator (TG) as a standby component for providing electricity during the blackouts and the second energy system is a grid-connected microgrid consisting of photovoltaic (PV) and battery energy storage (BES) as a standby component. Sensitivity analyses are conducted to investigate the survivability of both energy systems during the blackouts. The objective function minimizes total net present cost (NPC) and cost of energy (COE) by considering the defined constraints of the system for increasing the resiliency. Simulations are performed by HOMER, and results show that for having almost the same resilience enhancement in both systems, the second system, which is a grid-connected microgrid, indicates lower NPC and COE compared to the first system. More comparison details are shown in this paper to highlight the effectiveness and weakness of each resilient energy system.

7

Wilson, D. „Banishing blackouts [power system oscillations stability]“. Power Engineer 20, Nr. 2 (2006): 38. http://dx.doi.org/10.1049/pe:20060208.

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8

Wu, Yuan-Kang, Shih Ming Chang und Yi-Liang Hu. „Literature Review of Power System Blackouts“. Energy Procedia 141 (Dezember 2017): 428–31. http://dx.doi.org/10.1016/j.egypro.2017.11.055.

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9

Shao, Hongbo, Yubin Mao, Yongmin Liu, Wanxun Liu, Sipei Sun, Peng Jia, Fufeng Miao, Li Yang, Chang Han und Bo Zhang. „A Three-Stage Procedure for Controlled Islanding to Prevent Wide-Area Blackouts“. Energies 11, Nr. 11 (07.11.2018): 3066. http://dx.doi.org/10.3390/en11113066.

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Controlled islanding has been proposed as a last resort action to stop blackouts from happening when all standard methods have failed. Successful controlled islanding has to deal with three important issues: when, and where to island, and the evaluation of the dynamic stability in each island after islanding. This paper provides a framework for preventing wide-area blackouts using wide area measurement systems (WAMS), which consists of three stages to execute a successful islanding strategy. Normally, power system collapses and blackouts occur shortly after a cascading outage stage. Using such circumstances, an adapted single machine equivalent (SIME) method was used online to determine transient stability before blackout was imminent, and was then employed to determine when to island based on transient instability. In addition, SIME was adopted to assess the dynamic stability in each island after islanding, and to confirm that the chosen candidate island cutsets were stable before controlled islanding was undertaken. To decide where to island, all possible islanding cutsets were provided using the power flow (PF) tracing method. SIME helped to find the best candidate islanding cutset with the minimal PF imbalance, which is also a transiently stable islanding strategy. In case no possible island cutset existed, corresponding corrective actions such as load shedding and critical generator tripping, were performed in each formed island. Finally, an IEEE 39-bus power system with 10 units was employed to test this framework for a three-stage controlled islanding strategy to prevent imminent blackouts.

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Zhang, Fu Chao, und Jia Dong Huang. „Power System Cascading Failure Risk Assessment Model Based on Graph Theory“. Applied Mechanics and Materials 496-500 (Januar 2014): 2844–47. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.2844.

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In recent years, large-scale power blackouts occur frequently in power system, resulting in extremely serious economic losses and social impact [. Scholars from various countries have made various levels of analysis on the causes of widespread blackouts from different angles [2-.The results show that most of the fault are caused by the cascading failure, and the linkage and relevance between failures are typical of such events. Accordingly, to strengthen the analysis of cascading has important significances on preventing the occurrence of large-scale power blackouts.

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O. Alwan, Hayder, und Noor M. Farhan. „Load restoration methodology considering renewable energies and combined heat and power systems“. International Journal of Engineering & Technology 7, Nr. 2.6 (11.03.2018): 130. http://dx.doi.org/10.14419/ijet.v7i2.6.10138.

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Outages and faults cause problems in interconnected power system with huge economic consequences in modern societies. In the power system blackouts, black start resources such as micro combined heat and power (CHP) systems and renewable energies, due to their self-start ability, are one of the solutions to restore power system as quickly as possible. In this paper, we propose a model for power system restoration considering CHP systems and renewable energy sources as being available in blackout states. We define a control variable representing a level of balance between the distance and importance of loads according to the importance and urgency of the affected customer. Dynamic power flow is considered in order to find feasible sequence and combination of loads for load restoration.

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Chen, Chao-Rong, Wen-Ta Tsai und Hua-Yi Chen. „System Simulation and Implementation of SIPS in Taiwan“. Mathematical Problems in Engineering 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/184020.

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This study describes the system simulation and implementation of the system integrity protection schemes (SIPS) in an independent, intensive, and island-type power system. It also elucidates a smart grid plan to provide grid security in this power grid. The proposed SIPS can prevent blackouts that could otherwise result from the transient instability of N-3 contingencies and has been fully implemented and operated. The entire SIPS installation comprises two stages. The first-stage SIPS takes generator tripping system simulation and the second-stage SIPS involves generator tripping, load rejection, and bus-tie switching countermeasures. The proposed SIPS can prevent isolated power system blackout from extreme contingencies system and provide a valuable system simulation experience for similar independent power grids.

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ALI, Assist Prof Dr Inaam I., und Mohanad Sh Tarad AL-AASAM. „REDUCING SHORT CIRCUIT LEVELS BY USING SYSTEM SPLITTING STRATEGIES“. Al-Qadisiyah Journal for Engineering Sciences 11, Nr. 3 (31.01.2019): 309–31. http://dx.doi.org/10.30772/qjes.v11i3.563.

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Preliminary studies on Iraqi power system show a significant increase in the short circuit level at some of the grid substations and some power stations. This increasing results from the growth of the power generation and transmission systems in size and complexity. Islanding or splitting is dividing the power system into several islands inorder to reduce short circuit levels and avoiding blackouts. The main islanding problem is determining the location of proper splitting points and load balance and satisfaction of transmission capacity constraints for each islands.This paper mainly introduces new proposed splitting strategies of large-scale power systems by using (PSS™E version 30.3 PACKAGE PROGRAME), such that, make re-interconnection of 400KV super high voltage substation based on three-phase load flow to be minimum flow at splitting point and infeed fault current details method to control short circuit levels in Iraq power system without islanding the power system into isolated islands. Controlled islanding or splitting scheme is frequently considered as the final solution to avoid blackouts of power system.Simulation IEEE-25 bus and Iraqi power system used as the test systems for this method. Furthermore, simulation results show significant effectiveness on reducing short circuit levels with same time give stable splitting islands with same frequency for preventing the system blackouts.

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Tamronglak, S., S. H. Horowitz, A. G. Phadke und J. S. Thorp. „Anatomy of power system blackouts: preventive relaying strategies“. IEEE Transactions on Power Delivery 11, Nr. 2 (April 1996): 708–15. http://dx.doi.org/10.1109/61.489327.

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15

Khair, Abul, Mohd Rihan und Mohd Zuhaib. „Implementation of Controlled Islanding Scheme for Self-healing Smart Grid“. International Journal of Engineering & Technology 7, Nr. 3.12 (20.07.2018): 945. http://dx.doi.org/10.14419/ijet.v7i3.12.17608.

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With increase in deregulations and renewable sources of generation, the power system network is leading towards more geographical spread and interconnectedness. This causes significant challenges requiring on-line monitoring and control. It also provides a path for disturbances to propagate causing cascading failure, even blackouts. Wide area detection of potential island formation and controlled separation is considered as an effective tool against a blackout under severe disturbances. In the present work one line remaining algorithm has been utilized for implementation of controlled islanding in a section of Indian power grid.

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Sony, Michael, und V. Mariappan. „Stochastic Model for Preventing Blackouts“. International Journal of Operations Research and Information Systems 10, Nr. 1 (Januar 2019): 41–55. http://dx.doi.org/10.4018/ijoris.2019010103.

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Power system blackouts cause huge financial losses for the society and power utilities. Two types of blackouts have been identified. One involving load loss due to transmission lines reaching its limits and other involving failures of multiple transmission lines. Technologically advanced electricity transmission networks work in a financially just manner if a high rate of availability of the transmission networks is accomplished. Keeping this concept in mind, it is imperative to conduct the examination of transmission network availability, to design reliable electrical systems. This article discusses the stochastic availability modeling and analysis in transmission lines. The same is applied to a case of GED and the results obtained are discussed with the proper conclusion.

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Negnevitsky, Michael, Nikita V. Tomin und Christian Rehtanz. „Preventing Large-Scale Emergencies in Modern Power Systems: AI Approach“. Journal of Advanced Computational Intelligence and Intelligent Informatics 18, Nr. 5 (20.09.2014): 714–27. http://dx.doi.org/10.20965/jaciii.2014.p0714.

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In recent years, due to liberalization, power systems are being operated closer and closer to their limits. At the same time, they have increased in size and complexity. Both factors increase the risk of major power outages and blackouts. In emergency and abnormal conditions, a power system operator has to deal with large amounts of data. However, due to emotional and psychological stress, an operatormay not be able to respond to critical conditions adequately and make correct decisions promptly. Mistakes can damage very expensive power system equipment or worse lead to major emergencies and catastrophic situations. Intelligent systems can play an important role by alarming the operator and suggesting the necessary actions to be taken to deal with a given emergency. This paper outlines some experience obtained at the University of Tasmania, Australia, Energy Systems Institute, Russia and TU-Dortmund University, Germany in developing intelligent systems for preventing large-scale emergencies and blackouts in modern power systems.

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Bolbot, Victor, Gerasimos Theotokatos, Evangelos Boulougouris, George Psarros und Rainer Hamann. „A Combinatorial Safety Analysis of Cruise Ship Diesel–Electric Propulsion Plant Blackout“. Safety 7, Nr. 2 (14.05.2021): 38. http://dx.doi.org/10.3390/safety7020038.

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Diesel–Electric Propulsion (DEP) has been widely used for the propulsion of various ship types including cruise ships. Considering the potential consequences of blackouts, especially on cruise ships, it is essential to design and operate the ships’ power plants for avoiding and preventing such events. This study aims at implementing a comprehensive safety analysis for a cruise ship Diesel–Electric Propulsion (DEP) plant focusing on blackout events. The Combinatorial Approach to Safety Analysis (CASA) method is used to develop Fault Trees considering the blackout as the top event, and subsequently estimate the blackout frequency as well as implement importance analysis. The derived results demonstrate that the overall blackout frequency is close to corresponding values reported in the pertinent literature as well as estimations based on available accident investigations. This study deduces that the blackout frequency depends on the number of operating Diesel Generator (DG) sets, the DG set’s loading profile, the amount of electrical load that can be tripped during overload conditions and the plant operation phase. In addition, failures of the engine auxiliary systems and the fast-electrical load reduction functions, as well as the power generation control components, are identified as important. This study demonstrates the applicability of the CASA method to complex marine systems and reveals the parameters influencing the investigated system blackout frequency, thus providing better insights for these systems’ safety analysis and enhancement.

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Strunck, Christoph, und Christian Rehtanz. „Definition of Key Indicators to Identify Optimal Distribution Grid Restoration Strategies“. E3S Web of Conferences 209 (2020): 01001. http://dx.doi.org/10.1051/e3sconf/202020901001.

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Due to significant changes in the power energy system and extreme weather conditions as a result of the increasing impact of climate change, large scale blackouts become more likely. With the rising penetration of renewable energy sources in distribution grids and the shutdown of large conventional power plants, the system inertia and therefore the resilience is decreasing. This will have a significant influence on the provision of ancillary services in the future. Especially for grid restoration processes, new concepts are necessary to assure an optimal integration of the distributed energy resources to resupply a grid after a blackout. However, to identify and assess the capability of distribution grids to restore the grid operation to resupply their grid independently of the transmission system key indicators are necessary for an analysis. Hence, this paper introduces a key indicator system, which has the goal to address several challenges of a distribution grid restoration.

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Saffarian, A., und M. Sanaye-Pasand. „New Local Adaptive Load-shedding Methods to Mitigate Power System Blackouts“. Electric Power Components and Systems 40, Nr. 3 (02.01.2012): 348–68. http://dx.doi.org/10.1080/15325008.2011.635367.

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21

Seyedi, H., und M. Sanaye-Pasand. „New centralised adaptive load-shedding algorithms to mitigate power system blackouts“. IET Generation, Transmission & Distribution 3, Nr. 1 (01.01.2009): 99–114. http://dx.doi.org/10.1049/iet-gtd:20080210.

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22

Nor, N. M., N. S. Zemri, S. A. Daud, T. Ibrahim und H. Daud. „Development of an Automated Three-Phase Distribution Box System“. Indonesian Journal of Electrical Engineering and Computer Science 6, Nr. 2 (01.05.2017): 233. http://dx.doi.org/10.11591/ijeecs.v6.i2.pp233-240.

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Most electrical appliances require continuous power supply. For domestic use, crucial appliances such as refrigerator, aquarium and alarm system highly depend upon the continuity of power supply. However, if they are left without electricity due to power outage or blackouts caused by internal or external disturbance, the discontinuity of power supply could be a critical issue to some involving party. Blackouts may be due to short circuit, fault or the overloading of electricity mains. During power outage, Residual Current Device (RCD) detects fault currents from live to the neutral wire within circuit and will trip to prevent shock. This circumstance can increase safety when a house is left unoccupied. Be that as it may, the power will remain switched off until manually reset by man. Thus, this paper presented a new concept of Three-Phase distribution box system in order to overcome tripping problem. This system will be able to identify and isolate the fault using measurement of current flow into each Miniature Circuit Breaker (MCB) of appliances and current flowing out from each of the load. The measured current value will be compared and the maximum allowable difference is 30mA. If the current difference exceeds the maximum limit then the fault MCB will be detected. Hence RCD will be automatically close the circuit after determining the fault location via the motor operation to make sure of power stability and evade any property loss.

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Braun, Martin, Christian Hachmann und Jonas Haack. „Blackouts, Restoration, and Islanding: A System Resilience Perspective“. IEEE Power and Energy Magazine 18, Nr. 4 (Juli 2020): 54–63. http://dx.doi.org/10.1109/mpe.2020.2986659.

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24

Bruno, Sergio, Giovanni De Carne und Massimo La Scala. „Distributed FACTS for Power System Transient Stability Control“. Energies 13, Nr. 11 (05.06.2020): 2901. http://dx.doi.org/10.3390/en13112901.

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The high penetration of renewable energy sources, combined with a limited possibility to expand the transmission infrastructure, stretches the system stability in the case of faults. For this reason, operators are calling for additional control flexibility in the grid. In this paper, we propose the deployment of switchable reactors and capacitors distributed on the grid as a control resource for securing operations during severe contingencies and avoiding potential blackouts. According to the operating principles, the line reactance varies by switching on or off a certain number of distributed series reactors and capacitors and, therefore, the stabilizing control rule is based on a stepwise time-discrete control action. A control strategy, based on dynamic optimization, is proposed and tested on a realistic-sized transmission system.

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Dobson, Ian, Benjamin A. Carreras, Vickie E. Lynch, Bertrand Nkei und David E. Newman. „ESTIMATING FAILURE PROPAGATION IN MODELS OF CASCADING BLACKOUTS“. Probability in the Engineering and Informational Sciences 19, Nr. 4 (31.08.2005): 475–88. http://dx.doi.org/10.1017/s026996480505031x.

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We compare and test statistical estimates of failure propagation in data from versions of a probabilistic model of loading-dependent cascading failure and a power system blackout model of cascading transmission line overloads. The comparisons suggest mechanisms affecting failure propagation and are an initial step toward monitoring failure propagation from practical system data. Approximations to the probabilistic model describe the forms of probability distribution of cascade sizes.

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Zhao, Xiang Dong, Xin Zhao, Ming Jun Lv, Jian Guo Liu, Feng Zhen Liu und Yan Hui Sun. „Summary of the Stability Chanllenges and Safe Operation of Power Systems in View of Dispatching“. Advanced Materials Research 960-961 (Juni 2014): 1588–91. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.1588.

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The Internet and the gradual implementation of the continuous power grid market in recent years make the power system more complex under different operating environment. Safe and stable operation of power grids have become increasingly important . With the rapidf development of the grid and constant innovation, safe and stable operation also has a new requirement , because the rapid development of the power system brings more This paper analyzes the causes of blackouts and reviews security of the power system stability problems related to measures on the security and stability of the power system operation .

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Nadia, Awatif, Md Sanwar Hossain, Md Mehedi Hasan, Sinthia Afrin, Md Shafiullah, Md Biplob Hossain und Khondoker Ziaul Islam. „Determination of transmission reliability margin for brownout“. AIMS Energy 9, Nr. 5 (2021): 1009–26. http://dx.doi.org/10.3934/energy.2021046.

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<abstract> <p>Power shortage is a severe problem in developing countries that are rolling to blackout, but today smart grids have the scope to avoid entire blackouts by transforming them into brownouts. A brownout is an under-voltage condition where the AC supply drops below the nominal value (120 V or 220 V) by about 10%. In a power system network, power shortages or disturbances can occur at any time, and the reliability margin analysis is essential to maintain the stability of the system. Transmission reliability margin (TRM) is a margin that keeps the network secure during any occurrence of disturbance. This paper presents a new approach to compute TRM in the case of brownout. The detailed assessment of TRM largely depends on the estimation of the available transfer power (ATC). In this method, the ATC of the system is calculated considering the effect of alternating current (AC) and direct current (DC) reactive power (Q) flow (DCQF). The entire procedure is carried out for the multi-transaction IEEE-6 bus system, and the results are compared to the current efficiency justification method. Numerical results demonstrate that the proposed technique is an effective alternative for calculating the TRM and is valid compared to the existing technique.</p> </abstract>

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Gajare, Swaroop, J. Ganeswara Rao, O. D. Naidu und Ashok Kumar Pradhan. „Wide-area measurement system-based supervision of protection schemes with minimum number of phasor measurement units“. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, Nr. 2100 (10.07.2017): 20160295. http://dx.doi.org/10.1098/rsta.2016.0295.

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Cascade tripping of power lines triggered by maloperation of zone-3 relays during stressed system conditions, such as load encroachment, power swing and voltage instability, has led to many catastrophic power failures worldwide, including Indian blackouts in 2012. With the introduction of wide-area measurement systems (WAMS) into the grids, real-time monitoring of transmission network condition is possible. A phasor measurement unit (PMU) sends time-synchronized data to a phasor data concentrator, which can provide a control signal to substation devices. The latency associated with the communication system makes WAMS suitable for a slower form of protection. In this work, a method to identify the faulted line using synchronized data from strategic PMU locations is proposed. Subsequently, a supervisory signal is generated for specific relays in the system for any disturbance or stressed condition. For a given system, an approach to decide the strategic locations for PMU placement is developed, which can be used for determining the minimum number of PMUs required for application of the method. The accuracy of the scheme is tested for faults during normal and stressed conditions in a New England 39-bus system simulated using EMTDC/PSCAD software. With such a strategy, maloperation of relays can be averted in many situations and thereby blackouts/large-scale disturbances can be prevented. This article is part of the themed issue ‘Energy management: flexibility, risk and optimization’.

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Huang, Liping, Zhaoxiong Huang, Chun Sing Lai, Guangya Yang, Zhuoli Zhao, Ning Tong, Xiaomei Wu und Loi Lei Lai. „Augmented Power Dispatch for Resilient Operation through Controllable Series Compensation and N-1-1 Contingency Assessment“. Energies 14, Nr. 16 (05.08.2021): 4756. http://dx.doi.org/10.3390/en14164756.

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Research on enhancing power system resilience against extreme events is attracting significant attention and becoming a top global agenda. In this paper, a preventive augmented power dispatch model is proposed to provide a resilient operation. In the proposed model, a new N-1-1 security criterion is proposed to select disruptive N-1-1 contingency cases that might trigger cascading blackouts, and an iterative contingency assessment process based on the line outage distribution factor is proposed to deal with security constraints. In terms of optimization objectives, two objectives related to power flow on the transmission line are considered to reduce the possibility of overload outages. Controllable series compensation devices are also considered in the model to improve the power flow distribution. Case studies conducted on the modified IEEE 30-bus, 118-bus and Polish 2382-bus systems show that the power flow solution of the proposed power dispatch model can avoid some branches from undertaking excessively heavy loads, especially lines forecasted to be affected by extreme events. The results of blackout simulations through a hidden failure cascading outage simulation model show that the average power losses of the proposed model are reduced by around 40% in some cases as compared to the classical economic dispatch model.

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STUBNA, M. D., und J. FOWLER. „AN APPLICATION OF THE HIGHLY OPTIMIZED TOLERANCE MODEL TO ELECTRICAL BLACKOUTS“. International Journal of Bifurcation and Chaos 13, Nr. 01 (Januar 2003): 237–42. http://dx.doi.org/10.1142/s0218127403006492.

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The recently proposed Highly Optimized Tolerance (H.O.T.) model [Carlson & Doyle, 1999, 2000], which aims to describe the statistics of robust complex systems in uncertain environments, is compared with data from the Western United States (W.S.C.C.) power distribution system. We use for comparison a 15-year record of all power outages occurring on the grid, measured in the size of megawatts lost and the number of customers without service. In applying the model to the power grid data, we find that the problem of determining how the resources in the system scale with event size is nontrivial given the assumptions of the model and the information about how the power grid actually operates. Further, we observe that the model agrees closely with the W.S.C.C. data for the megawatts but not the customers, and consequently propose that the assumption in the model of optimal resource distribution is not valid in general when more than one measure of event size is used. A modified H.O.T. model which allows for resource misallocation is introduced and we find that this model can be made to fit both data sets reasonably well.

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L. Bekri, O., und F. Mekri. „Improvement of large power system with facts devices placement to maxim-IZE the system load ability“. International Journal of Engineering & Technology 7, Nr. 2.28 (16.05.2018): 381. http://dx.doi.org/10.14419/ijet.v7i2.28.13215.

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Voltage instabilities and/or collapses have been recognized as one of the major causes of power system blackouts. The main objective of this paper is to provide some solutions to prevent large power systems from voltage collapse. The FACTS (Flexible AC Transmission Sys-tems) devices placement gives new opportunities for enhancing voltage stability. The calculation of the loadability point is based on the con-tinuation power flow technique (CPF) to choosing the optimal placement of STATCOM (Static Synchronous Compensator) in order to improve voltage stability by increasing the loading parameter, maintaining bus voltages at desired level and minimizing losses in a power system network.A 39-bus New England power system is chosen as test case in order to illustrate this approach. The obtained results show the efficiency of the proposed method for the planning of the Static Synchronous Compensator optimal placement and the voltage stability enhancement.

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Shrestha, Ashish, und Francisco Gonzalez-Longatt. „Frequency Stability Issues and Research Opportunities in Converter Dominated Power System“. Energies 14, Nr. 14 (11.07.2021): 4184. http://dx.doi.org/10.3390/en14144184.

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Stable power supply has become a crucial thing in the current era of technology and automation. Although the power system has multiple stability issues and causes, frequency fluctuation plays a vital role in normal operation, whereby a system with significant frequency deviation can lead to the needless blackouts of the whole power system. With the rapid growth in power electronic converter (PEC)-based technologies and the huge penetration of nonsynchronous generators, the modern power system is becoming more complex by the day. This paper provides a comprehensive study on the stability issues that occur in modern power systems, mainly due to PEC-based technology integration. The in-depth reasons and the impacts of unstable power systems, along with their controlling techniques, are discussed to generate a clear understanding. Furthermore, the importance of frequency stability in a power system is discussed with respect to some important events that occurred in the past. This paper also discusses some potential techniques that could be performed to overcome the existing and/or upcoming challenges in the upgrading power system.

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Wehenkel, L., C. Lebrevelec, M. Trotignon und J. Batut. „A Probabilistic Approach to the Design of Power System Protection Schemes Against Blackouts“. IFAC Proceedings Volumes 30, Nr. 17 (August 1997): 471–76. http://dx.doi.org/10.1016/s1474-6670(17)46450-0.

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Carreras, Benjamin A., Eder Batista Tchawou Tchuisseu, José M. Reynolds-Barredo, Damià Gomila und Pere Colet. „Effects of demand control on the complex dynamics of electric power system blackouts“. Chaos: An Interdisciplinary Journal of Nonlinear Science 30, Nr. 11 (November 2020): 113121. http://dx.doi.org/10.1063/5.0011187.

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Brehovská, Lenka, Veronika Nešporová und David Řehák. „Approach to Assessing the Preparedness of Hospitals to Power Outages“. TRANSACTIONS of the VŠB – Technical University of Ostrava, Safety Engineering Series 12, Nr. 1 (28.03.2017): 30–40. http://dx.doi.org/10.1515/tvsbses-2017-0005.

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Abstract Within the secondary impacts of electricity blackouts, it is necessary to pay attention to facilities providing medical care for the population, namely the hospitals. Hospitals represent a key position in the provision of health care also in times of crisis. These facilities must provide constant care; it is therefore essential that the preparedness of such facilities is kept at a high level. The basic aim of this article is to analyse the preparedness of hospitals to power outages (power failures, blackouts) within a pilot study. On that basis, a SWOT analysis is used to determine strengths and weaknesses of the system of preparedness of hospitals to power outages and solutions for better security of hospitals are defined. The sample investigated consists of four hospitals founded by the Regional Authority (hospitals Nos. 1-4) and one hospital founded by the Ministry of Health of the Czech Republic (hospital No. 5). The results of the study shows that most weaknesses of the preparedness of hospitals are represented by inadequately addressed reserves of fuel for the main backup power supply, poor knowledge of employees who are insufficiently retrained, and old backup power supplies (even 35 years in some cases).

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Zhang, Fu Chun, Jia Dong Huang, Xin Sun und Qing Jie Zhou. „The Research on Risk Assessment Model of Cascading Failures in Power System“. Applied Mechanics and Materials 373-375 (August 2013): 1312–17. http://dx.doi.org/10.4028/www.scientific.net/amm.373-375.1312.

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In order to prevent large scope blackouts, the paper has established a model of power system cascading failures from the perspective of risk .Taking both the load of branch and the power flow changes into account, the model defines the probability of branch outage which can reflect the real-time operating condition. The consequences severity of cascading failure is measured by bus low voltage, power line overload level and the amount of isolated loads. In the process of searching fault link, the paper uses the structure transmission importance of branch to determine the next breaking branch, which can speed the search of the cascading failure mode. The simulation of the IEEE 39-node system shows the effectiveness of the method.

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Carreras, B. A., D. E. Newman, I. Dobson und A. B. Poole. „Evidence for Self-Organized Criticality in a Time Series of Electric Power System Blackouts“. IEEE Transactions on Circuits and Systems I: Regular Papers 51, Nr. 9 (September 2004): 1733–40. http://dx.doi.org/10.1109/tcsi.2004.834513.

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Kamis, Zalina, Mohd Ruddin Ab.Ghani, Muhammad Nizam Kamarudin, Hairol Nizam Mohd Shah und Jano Zanariah. „A Review on SVC control for power system stability with and without auxiliary controller“. Bulletin of Electrical Engineering and Informatics 8, Nr. 3 (01.09.2019): 761–68. http://dx.doi.org/10.11591/eei.v8i3.1318.

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Since the beginning of the last century, power system stability has been recognized as a vital problem in securing system operation. Power system instability has caused many major blackouts. This paper reviewed the previous technical works consisting of various methods of optimization in controlling power system stability. The techniques presented were compared to optimize the control variables for optimization of power system stability. Power system stability enhancement has been investigated widely in literature using different ways. This paper is focusing on SVC performance for enhancing power system stability either through SVC controlled itself or SVC controlled externally by other controllers. Static VAR compensators (SVCs) are used primarily in power system for voltage control as either an end in itself or a means of achieving other objectives, such as system stabilization.The analysis on performance of the previous work such as advantages and findings of a robust method approach in each technique was included in this paper.

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Peake, David, James Black, Elias Kumbakumba, Sheillah Bagayana, Celestine Barigye, Peter Moschovis, Ivan Muhumuza et al. „Technical results from a trial of the FREO2 Low-Pressure Oxygen Storage system, Mbarara Regional Referral Hospital, Uganda“. PLOS ONE 16, Nr. 3 (09.03.2021): e0248101. http://dx.doi.org/10.1371/journal.pone.0248101.

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Increased access to reliable medical oxygen would reduce the global burden of pneumonia. Oxygen concentrators have been shown to be an effective solution, however they have significant drawbacks when used in low-resource environments where pneumonia burden is the heaviest. Low quality grid power can damage oxygen concentrators and blackouts can prevent at-risk patients from receiving continual oxygen therapy. Gaps in prescribed oxygen flow can result in acquired brain injuries, extended hypoxemia and death. The FREO2 Low-Pressure Oxygen Storage (LPOS) system consists of a suite of improvements to a standard oxygen concentrator which address these limitations. This study reports the technical results of a field trial of the system in Mbarara, Uganda. During this trial, oxygen supplied from the LPOS system was distributed to four beds in the paediatric ward of Mbarara Regional Referral Hospital. Over a three-month period, medical-grade oxygen was made available to patients 100% of the time. This period was sufficient to quantify the ability of the LPOS system to deal with blackouts, maintenance, and an unscheduled repair to the LPOS store.

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Yoon, J., und S. Song. „Future Directions for Power System Interconnection from Korea’s Perspective“. Energy Systems Research, Nr. 4(12) (01.02.2021): 48–53. http://dx.doi.org/10.38028/esr.2020.04.0006.

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The power system interconnection between Northeast Asian countries has been discussed since 2000 but has not been realized to date due to various obstacles. This paper specifies the expected future energy policy, long-term energy supply plan, and necessity of power interconnection from the Korean viewpoint, including the climate change agreement. There are very many interconnection scenarios presented by various institutes in NEA countries now. These studies contain the overall preliminary feasibility results but do not consider the environmental effects, energy security, and market reforms. Do these existing studies show how we could interconnect specific countries? This paper discusses the trading potentials for green energy utilization between countries and some obstacles to be removed to promote the energy interconnection projects from technical, economic, marketable, and energy security standpoints. Especially, energy security in terms of politics, as well as vulnerability characteristics of renewable energy, could cause the interconnected system blackouts. These could be a serious obstacle to realization and continuous stable operation of these interconnection projects. Finally, this paper will specify the future directions and possible scenarios for power system interconnection by integrating these issues comprehensively from Korea's perspective.

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Moradzadeh, Mohammad, und René Boel. „Voltage Coordination via Communication in Large-Scale Multi-Area Power Systems. Part I: Principal“. Advanced Materials Research 433-440 (Januar 2012): 7175–82. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.7175.

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This two-part paper deals with the coordination of the control actions in a network of many interacting components, where each component is controlled by independent control agents. As a case study we consider voltage control in large electric power systems, where ever-increasing pressures from the liberalization and globalization of the electricity market has led to partitioning the power system into multiple areas each operated by an independent Transmission System Operator (TSO). Coordination of local control actions taken by those TSOs is a very challenging problem as poorly coordinated operation of TSOs may endanger the power system security by increasing the risk of blackouts. This coordination problem involves many other issues such as communication, abstraction and last but not least optimization. This first part of the paper is devoted to the principals of the coordination control, addressing some of those issues using as a case study the problem of coordination control for avoiding voltage collapse in large-scale multi-area power systems.

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Kiruthika, M., und S. Bindu. „Classification of Electrical Power System Conditions with Convolutional Neural Networks“. Engineering, Technology & Applied Science Research 10, Nr. 3 (07.06.2020): 5759–68. http://dx.doi.org/10.48084/etasr.3512.

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Undesirable operation of a distant relay at the occurrence of stressed conditions is a reason for blackouts. There are a few computational intelligent methods available in the literature for avoiding relay maloperations. However, because of variations in the system parameters and expansions of the network, the performance of these techniques can be degraded. To solve this issue, data mining approaches have been introduced. The existing data mining approaches need improvement in terms of accuracy and error rate while discriminating fault and stressed conditions. In this paper, a Convolutional Neural Network (CNN) based classifier is proposed for identifying various faults and differentiating fault and power swing situations. The data are collected from the IEEE-9 bus system by Phasor Measurement Units (PMU) and the proposed CNN classifier model classifies system conditions like normal, fault, and power swing. The outcome shows that the classifier has high accuracy and low error rate compared to other classification models such as Naïve Bayes, Decision Tree, and K-Nearest Neighbor. Furthermore, the proposed CNN model is validated with the use of TensorFlow framework to demonstrate its superior performance.

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Osmani, Khaled, Ahmad Haddad, Thierry Lemenand, Bruno Castanier und Mohamad Ramadan. „Material Based Fault Detection Methods for PV Systems“. Key Engineering Materials 865 (September 2020): 111–15. http://dx.doi.org/10.4028/www.scientific.net/kem.865.111.

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The overall efficiency of a PV system is strongly affected by the PV cell raw materials. Since a reliable renewable energy source is expected to produce maximum power with longest lifetime and minimum errors, a critical aspect to bear in mind is the occurrence of PV faults according to raw material types. The different failure scenarios occurring in PV system, decrease its output power, reduce its life expectancy and ban the system from meeting load demands, yielding to severe consecutive blackouts. This paper aims first to present different core materials types, material based fault occurring on the PV cell level and consequently the fault detection techniques corresponding to each fault type.

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Wang, Qiang, Shu Ting Song, Hui Ming Zhang und Da Hai Yao. „Fuzzy Comprehensive Assessment Method is Based on the Transmission Lines of the Analytic Hierarchy Process Sewage Flash“. Applied Mechanics and Materials 347-350 (August 2013): 1907–14. http://dx.doi.org/10.4028/www.scientific.net/amm.347-350.1907.

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Transmission line flashing will cause large area and long time of blackouts,it happens in the working voltage,and it poses serious threat to the electric power system. With the development of industry,the increase of power grid capacity and rated voltage level,there are more and more flashing accidents occurred in the power system of power transmission and transformation equipment external insulation,also the damage that they bring about to our economy is getting larger.Aiming at a series of problems caused by transmission line flashing,this paper comes up with an assessment method of transmission line flashing,it improves the forecast accuracy and efficiency so as to ensure the safety operation of transmission.

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Kebede, Fitsum-Salehu, Jean-Christophe Olivier, Salvy Bourguet und Mohamed Machmoum. „Reliability Evaluation of Renewable Power Systems through Distribution Network Power Outage Modelling“. Energies 14, Nr. 11 (31.05.2021): 3225. http://dx.doi.org/10.3390/en14113225.

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Intermittent power interruptions and blackouts with long outage durations are very common, especially on weak distribution grids such as in developing countries. This paper proposes a hybrid photovoltaic (PV)-battery-system sizing optimization through a genetic algorithm to address the reliability in fragile grids measured by the loss of power supply probability (LPSP) index. Recorded historical outage data from a real stochastic grid in Ethiopia and measured customer load is used. The resulting hybrid-system Pareto solutions give the flexibility for customers/power utilities to choose appropriate sizes based on the required reliability level. To evaluate the sizing solutions’ robustness, this work considers and compares grid outage modeling through two different approaches. The first is a Markov model, developed to be minimally implemented with limited outage data available. The second is a Weibull model, commonly used to describe extreme phenomena and failure analysis. It is more faithful in reproducing the dispersion of outage events. Using these models, the effectiveness and performance of the PV-battery system is verified on a large number of simulated outage scenarios, to estimate the real performance of the optimized design. It leads to a more accurate evaluation of the behavior of a renewable power system to a weak and unreliable electrical grid.

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Packiasudha, M., und S. Suja. „FACT Device for Reactive Power Compensation in the Deregulated Electrical Power Environment“. International Journal of Power Electronics and Drive Systems (IJPEDS) 6, Nr. 4 (01.12.2015): 730. http://dx.doi.org/10.11591/ijpeds.v6.i4.pp730-735.

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In the deregulating electricity market, many private sector power producers are participating actively. With growing number of the wind mills and solar power generation, the reactive power production will be more because of induction generator and inductive type load. Many blackouts have happened in the past decades due to more reactive power which lead to a decrease in the magnitude of real power. It is very essential to compensate the reactive power, increase the real power flow in the transmission line, increase the transmission efficiency, improve the system stability and be in a safer place to save the fossil fuels for the future. In this paper the importance of reactive power and its various compensation techniques are applied to a five bus deregulated test case modeled and analyzed. The simulations were done using Matlab Simulink, for various FACT controllers such as STATCOM, SVC, SSSC and UPFC compensation and the results were tabulated and compared.

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Sanchez Garciarivas, Rafael, Diego Rasilla Gonzalez, Javier Agustin Navarro, Luis Arturo Soriano, José de Jesús Rubio, Maria Victoria Gomez, Victor Garcia und Jaime Pacheco. „VSC-HVDC and Its Applications for Black Start Restoration Processes“. Applied Sciences 11, Nr. 12 (18.06.2021): 5648. http://dx.doi.org/10.3390/app11125648.

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System reliability is a measure of an electric grid system’s ability to deliver uninterrupted service at the proper voltage and frequency. This property of the electric system is commonly affected by critical processes, such as a total blackout. The electric system restoration is a complex process which consists of returning generators, transmission system elements, and restoring load following an outage of the electric system. However, the absence of a generator or unit of black start capabilities may worsen the duration and effects of blackouts, having severe consequences. Black start capability is important as it can reduce the interruption time, decrease the economic loss, and restart the power supply fast and efficiently. In recent years, several works have reported advances about the High Voltage Direct Current (HVDC) technology based on the Voltage-Source Converter (VSC) as an attractive and promising technology to increase black start capability. This paper is a review of the current studies of VSC-HVDC as black start power and discusses the advantages and limitations of recent methods. The major points addressed in this paper are as follows: the current theoretical approach of the black start process and the used HVDC technologies, the advantages of VSC-HVDC as black start power, a compressive review of the literature about the black start capabilities using VSC-HVDC technologies, and a description of the main methods recently used to provide an enhancement for restoration processes. Finally, this paper discusses new challenges and perspectives for VSC-HVDC links in order to provide an enhancement for restoration processes.

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Flaih, Firas M. F., Lin Xiangning, Samir M. Dawoud und Mohammed R. Almallah. „Cost Analysis of Hybrid Restructuration for Distribution System to Improve Voltage and Minimize Losses“. TELKOMNIKA Indonesian Journal of Electrical Engineering 16, Nr. 3 (01.12.2015): 431. http://dx.doi.org/10.11591/tijee.v16i3.1633.

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<p>Current situation in Iraq had led to extensive blackouts which needs an expansion in generation capacity. On the other hand the government has reduced the budget allocated for energy resource development and it seems this situation will sustain for the coming years. So the fulfilment of the load demand is the biggest challenge for the ministry of electricity with limited budget. In this paper the authors have proposed a method to reduce the power losses and therefore improve the voltage profile for low voltage (LV) distribution system that results in reduction of blackouts. The method involves the repositioning of the distribution transformer (DTR) from the existing location and the replacement of the overhead conductor cross section area for an existing low voltage distribution system (LVDS). This method has been applied to a 20-node low voltage radial distribution network in the general directorate of north distribution electricity (GDNDE), Iraq, where voltage profile and losses are unsatisfactory. Results demonstrate the effectiveness of the proposed method also in terms of the economic feasibility. It is observed that the system average voltage profile is improved by 15%, tail end voltage enhanced by 19.7% and losses are reduced by 78% for existing the LVDS.</p>

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Jouini, Houda, Kamel Jemai und Souad Chebbi. „Voltage Stability Control of Electrical Network Using Intelligent Load Shedding Strategy Based on Fuzzy Logic“. Mathematical Problems in Engineering 2010 (2010): 1–17. http://dx.doi.org/10.1155/2010/341257.

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As a perspective to ensure the power system stability and to avoid the vulnerability leading to the blackouts, several preventive and curative means are adopted. In order to avoid the voltage collapse, load shedding schemes represent a suitable action to maintain the power system service quality and to control its vulnerability. In this paper, we try to propose an intelligent load shedding strategy as a new approach based on fuzzy controllers. This strategy was founded on the calculation of generated power sensitivity degree related to those injected at different network buses. During the fault phase, fuzzy controller algorithms generate monitor vectors ensuring a precalculated load shedding ratio in the purpose to reestablish the power balance and conduct the network to a new steady state.

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Saleem, Adeel, Atif Iqbal, Kashif Mehmood, Muhammad Adnan Samad, Muhammad Aftab Hayat und Usamah Manzoor. „Modelling and Implementation of Microprocessor Based Numerical Relay for Protection Against Over/Under Current, Over/Under Voltage“. Journal of Computational and Theoretical Nanoscience 17, Nr. 2 (01.02.2020): 1332–38. http://dx.doi.org/10.1166/jctn.2020.8809.

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This paper includes the design and implementation of Numerical Relay that can protect the equipment against over-voltage, over-current and under voltage. Although, every power system is subjected to faults and these faults can severe damage to the power system. Therefore, it is necessary to observe and resolve in time to avoid a large damage such as blackouts. For this purpose, there should be some sensing devices, which give signals to the circuit breakers for preventing of power system damages. The multipurpose relays have much importance role in power system for sensing and measuring the amplitude of faults. Numerical relay provides settings of over-current, overvoltage and under voltage values. Simulations have been carried out using Proteus software along with tested on hardware with Arduino Uno Microcontroller that proves the working and operation of numerical relay.

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