Showing papers in "IEEE Power & Energy Magazine in 2012"
TL;DR: Most discussions about ac versus dc electricity include a retelling of the famous technical and commercial battle between Edison and Westinghouse/Tesla as mentioned in this paper, a story about everything from electrocuting elephants at state fairs to the ambitious work of electrifying both urban and rural America.
Abstract: Most discussions about ac versus dc electricity include a retelling of the famous technical and commercial battle between Edison and Westinghouse/Tesla. It's a story about everything from electrocuting elephants at state fairs to the ambitious work of electrifying both urban and rural America. It's the tale of one of man's greatest engineering feats. It tells of a centralized power generation system based on the dominant use of incandescent light bulbs and ac constant-speed motors. In the end though, it is a retelling of history and unfortunately, it is a history that doesn't project.
239 citations
TL;DR: In this paper, the authors argue that the transition from ac to dc is not only necessary but inevitable and that the majority of the load base is natively dc at some point soon.
Abstract: We are on the cusp of a great technology transition in power distribution from ac to dc at the edge of the grid Data centers are merely one of the first industries to embrace the coming tide The transition on the customer side of the meter is on the order of what happened over the last 40 years with personal computers, the Internet, and cell phones The predominant use of power electronics in almost everything we buy new today makes them natively dc devices As a society, we could be more efficient and sustainable if we were to skip the last ac-to-dc conversion At some point soon, when the majority of the load base is natively dc, we reach a tipping point where ac and hot power converter “bricks” on everything are no longer sustainable Add to this distributed generation, distributed energy storage, and renewable carbon-free power sources that prefer dc, and one can conclude that the transition is not only necessary but inevitable
237 citations
TL;DR: In this paper, the authors present the communication requirements of the smart grid and identify the main technical challenges that need to be tackled, and the only viable way to fulfill these requirements is to design a new communication architecture that can support smart grid services and control operations.
Abstract: Making the smart grid a reality will entail communication capabilities that do not exist in current power grids and their legacy control systems. New grid elements such as distributed energy generation and PHEVs will necessitate changes in these existing communication networks. These changes will be dictated by the need for new control operations that will allow efficient management of these new elements and that cannot be supported by the existing communication infra structure. Moreover, the smart grid will let households man age energy usage more efficiently through AMI and HEMSs. The realization of these systems will require pushing communication networks far out from the network core and deep into homes and buildings. We have presented the communication requirements of the smart grid, and we have identified the main technical challenges that need to be tackled. The only viable way to fulfill these requirements is to design a new communication architecture that can support smart grid services and control operations. This future communication architecture will need to take advantage of the recent progress made in communication technologies and protocols. It will require the introduction of communications technologies that were not considered in the past. In addition, this communication architecture will need to be reliable, scalable, and extendable to future smart grid services and applications.
208 citations
TL;DR: In this paper, the first commercial transmission link between the island of Gotland and the Swedish mainland was introduced, and more than 100 HV dc transmission systems have been installed around the world.
Abstract: Developed to meet a combination of technical and economic considerations, high-voltage dc (HV dc) was launched in 1954 with the first commercial transmission link between the island of Gotland and the Swedish mainland. Since then, HV dc technology has advanced dramatically, and more than 100 HV dc transmission systems have been installed around the world.
149 citations
TL;DR: In this paper, a strong case is made for intermeshed ac and dc networks, with new concepts emerging at the mediumvoltage (MV) level for MV dc infrastructure developments.
Abstract: Corporate research centers, universities, power equipment vendors, end users, and other market participants around the world are beginning to explore and consider the use of dc in future transmission and distribution system applications. Recent developments and trends in electric power consumption indicate an increasing use of dc-based power and constant power loads. In addition, growth in renewable energy resources requires dc interfaces for optimal integration. A strong case is being made for intermeshed ac and dc networks, with new concepts emerging at the medium-voltage (MV) level for MV dc infrastructure developments.
130 citations
TL;DR: A power grid is a critical infrastructure that relies on supervisory control and data acquisition systems for monitoring, control, and operation and the use of firewalls has become a widely adopted access control method against intruders.
Abstract: A power grid is a critical infrastructure that relies on supervisory control and data acquisition (SCADA) systems for monitoring, control, and operation. On top of the power infrastructure reside layers of information and communications technology (ICT) that are interconnected with electric grids. The cyber and power infrastructures together constitute a large, complex cyberphysical system. ICTs on the power grids have evolved from isolated structures into open and networked environments based on TCP/IP and Ethernet. The technology is known to be vulnerable with respect to cyberintrusions. As ICTs of the power infrastructure have evolved into highly connected network environments, the use of firewalls has become a widely adopted access control method against intruders. Firewalls do not guarantee cybersecurity, however. The misconfiguration of company firewalls has been reported. Even if the configuration of a firewall is correct, it is still vulnerable because firewalls are not able to detect insider attacks and connections from the trusted side. Hence, solutions based solely on firewalls can be inadequate.
106 citations
TL;DR: In this paper, the deployment of phasor measurement unit (PMU) technology, in combination with recently developed methodologies for tracking voltage behavior, has resulted in improved real-time voltage monitoring, protection, and control.
Abstract: As the electrical utility industry addresses energy and environmental needs through greater use of renewable energy, storage, and other technologies, power systems are becoming more complex and stressed. Increased dynamic changes that require improvements in real-time monitoring, protection, and control increase the complexity of managing modern grids. In an effort to ensure the secure operation of power systems, more attention is being given to voltage management. Voltage management includes addressing voltage stability and fault-induced delayed voltage recovery (FIDVR) phenomena. Deployment of phasor measurement unit (PMU) technology, in combination with recently developed methodologies for tracking voltage behavior, has resulted in improved real-time voltage monitoring, protection, and control.
94 citations
TL;DR: The modern power grid is one of the most complex engineering machines in existence as mentioned in this paper, and the U.S. National Academy of Engineering has voted to recognize the grid as the supreme engineering achievement of the 20th century.
Abstract: The modern power grid is one of the most complex engineering machines in existence. Its millions of components comprise the entire electricity supply chain, from point of generation to the end consumer. Each of these pieces must work together, reliably, 24 hours a day, seven days a week, to power our homes and businesses. In 2001, the U.S. National Academy of Engineering voted to recognize the grid as the supreme engineering achievement of the 20th century. Making matters more complex is the reality that grid conditions are continually changing every second, every minute, and every hour of the day. Changes in demand for electricity necessitate instantaneous changes in electricity production; consequently, voltages, currents, and power flows are dynamically changing at all times across the electricity supply chain.
87 citations
TL;DR: A successful terrorist attempt to disrupt the power delivery system could have adverse effects on national security, the economy, and the lives of every citizen as mentioned in this paper, and a successful terrorist attack on the electric system is fundamental to national and international economic systems, security, and quality of life.
Abstract: The existing power delivery system is vulnerable to both natural disasters and intentional attack. A successful terrorist attempt to disrupt the power delivery system could have adverse effects on national security, the economy, and the lives of every citizen. Secure and reliable operation of the electric system is fundamental to national and international economic systems, security, and quality of life.
75 citations
TL;DR: It is no longer possible to maintain the N-1 security of the system at all moments by using only preventive actions, and the number of hours during which the system requires corrective actions to be secure is increasing.
Abstract: Over the last ten years, we have heard so often in conferences, seminars, and workshops that the power system will soon be operated very near to its limits that this statement has become a cliche. Unfortunately, it is no longer possible to comply with the classical preventive N-1 security standards during all of the hours in a year. The system is indeed no longer able to survive all single faults without postfault actions. More and more corrective (i.e., postfault) actions are defined and prepared by operators, and the cliche is now a reality, as a matter of fact. To be more precise, it is no longer possible to maintain the N-1 security of the system at all moments by using only preventive actions, and the number of hours during which the system requires corrective actions to be secure is increasing. More and more, new sp ecial protection schemes (SPSs) are deployed to implement some of these corrective actions automatically. Devices such as phase-shifting transformers (PSTs) and static var compensators (SVCs) are added in the system to increase its controllability. As a result, the system becomes more and more complex.
67 citations
TL;DR: A growing group of engineers, grid operators, and regulatory agencies believe that energy storage will be a critical component of the "grid of the future" as discussed by the authors, and the development of large-scale energy storage technologies is accelerating.
Abstract: A fundamental truth of the grid has been that electricity must be generated at the precise moment it is demanded. It is the ultimate “just in time” system, where the laws of physics prevent carrying inventory. This characterization is under challenge, as the development of large-scale energy storage technologies is accelerating. A growing group of engineers, grid operators, and regulatory agencies believe that energy storage will be a critical component of the “grid of the future.” Over the past several decades, large-scale hydro and pumped hydro storage facilities dominated the energy storage landscape. Today, new and evolving battery chemistries, primarily for electric vehicle and backup power applications, are emerging as potential solutions for some of the challenges that face the grid today. Both batteries and high-speed mechanical flywheels-connected to the grid through power electronics-are enabling smaller and more modular energy storage systems. These storage systems are being considered for a variety of applications, from time-shifting wind.
TL;DR: The intelligent integration of wind power into the existing electricity supply system will be an important factor in the future energy supply in many countries, and new methods of balancing supply and demand are necessary.
Abstract: The intelligent integration of wind power into the existing electricity supply system will be an important factor in the future energy supply in many countries. Wind power generation has characteristics that differ from those of conventional power generation. It is weather dependent in that it relies on wind availability. With the increasing amount of intermittent wind power generation, power systems encounter more and more short-term, unpredicted power variations. In the power system, supply and demand must be equal at all times. Thus, as levels of wind penetration into the electricity system increase, new methods of balancing supply and demand are necessary.
TL;DR: The most colorful response I have received was a note from a Canadian engineer who had reason to question the seemingly unimpeachable presumption that dc had long since disappeared from the distribution scene.
Abstract: This spring I published an article in MIT's Technology Review magazine, Edison's Revenge: The Rise of DC Power, predicting that dc might once again flow through the power distribution grids that deliver electricity to power consumers. It is an improbable scenario in the view of many power engineers, so I half expected some blowback. The most colorful response I received, however, was a note from a Canadian engineer who had reason to question the seemingly unimpeachable presumption that dc had long since disappeared from the distribution scene.
TL;DR: In this article, the authors propose a high-bandwidth and highly available networked communication system to overlay the transmission system topology in order to enable the control and protection of the grid.
Abstract: IT IS GENERALLY RECOGNIZED THAT A HIGH-BANDWIDTH and highly available networked communication system should overlay the transmission system topology in order to enable the control and protection envisaged today to make the grid more efficient and more reliable. The specifications for such a communication system have been difficult to develop, however, because it needs to support a great variety of applications, many of which have not yet been developed. Organizations such as the North American SynchroPhasor Initiative (NASPI) are trying to build on this vision of a communication system that can utilize phasor measurement data to initiate fast controllers, including flexible alternating current transmission system (FACTS) devices.
TL;DR: In this paper, the authors present a white paper on the challenges of smart grid R&D, demonstration, and eventual deployment, where four tasks are considered crucial to smart grid deployment.
Abstract: This article represents an edited version of opinions expressed in an extensive white paper created by many individuals associated with the Power Systems Engineering Research Center (PSERC) of the National Science Foundation (NSF) and posted on PSERC's Web site, www.pserc. org. The four tasks described above are considered crucial to smart grid R&D, demonstration, and eventual deployment. As learning and innovation occur during the course of a demonstration, changes may be needed in the architecture, the components, and the way they are integrated operationally. The goal is to acquire the best information possible for the eventual decisions on whether and how an integrated smart grid solution should be implemented, so adjusting demonstrations as needed to provide that information is very appropriate. It is also important that demonstrations be designed and implemented to gain the knowledge needed for a system wide deployment of a smart grid. The bulk transmission system should be included in the design. There are a great number of unknowns in moving toward the national goal of a low-carbon economy. That uncertainty can be reduced by effectively designed large-scale demonstrations drawing on the results of prior R&D efforts.
TL;DR: In this article, the first MT HVDC networks can be seen as initial building blocks on the way to a larger offshore grid, and the benefits of larger intercontinental grids are being demonstrated in several ongoing studies.
Abstract: HVdc and cable technologies exist today that permit offshore integration and planning of point-to-point dc links that can be expanded into HVdc grids. Several VSC HVdc links are now in operation offshore in the harsh North Sea environment. Following the rapid increase in power transmission capacity and loss reduction, several new projects in the gigawatt range are in the construction phase. The benefits of larger intercontinental grids are being demonstrated in several ongoing studies. The first MT HVdc networks can therefore be seen as initial building blocks on the way to a larger offshore grid.
TL;DR: The deployment of a continent- wide wide area measurement system (WAMS) is an important part of the solution to these complex problems, but it faces challenges with respect to communications and security.
Abstract: Deregulation, market transactions, congestion management, and the separation of functions have created increasing complexity that is making it difficult to maintain situational awareness and supervision of power system performance over large areas. Past reliability events (such as blackouts) have highlighted the need for better situational awareness and advanced applications to improve planning, operations, and maintenance. The deployment of a continent- wide wide area measurement system (WAMS) is an important part of the solution to these complex problems, but it faces challenges with respect to communications and security.
TL;DR: There is an increasing amount of evidence showing that attackers are now focusing on control systems, operating with varying motivations and intentions.
Abstract: This article discusses cybersecurity and the modern electric grid. There is an increasing amount of evidence showing that attackers are now focusing on control systems, operating with varying motivations and intentions.
TL;DR: The interconnected electric power grid is the single largest and most complex machine in the world as mentioned in this paper, and power outages, even for a short interval, have a very low probability but an enormous impact.
Abstract: The interconnected electric power grid is the single largest and most complex machine in the world. Power outages, even for a short interval, have a very low probability but an enormous impact. Transmission systems around the world are facing increasing load demands, and system elements are being pushed toward their thermal limits. Wide-area power trading with varying supply and load patterns is contributing to the ever-increasing congestion. The power grid of the future must be secure, cost effective, and environmental friendly yet reliably integrated and built with intelligent solutions and innovative technologies. High-voltage dc (HVDC) transmission systems are a proven tool in tackling these challenges.
TL;DR: A set of "universal truths" that are generally applicable to all power grids seeking to integrate more wind energy are described and a few specific examples are provided, emphasizing the unique perspectives and experiences of systems in Europe, China, and North America.
Abstract: This article summarizes some of the key lessons. We first describe a set of "universal truths" that are generally applicable to all power grids seeking to integrate more wind energy. We then provide a few specific examples, emphasiz ing the unique perspectives and experiences of systems in Europe, China, and North America.
TL;DR: In this article, a Synchrophasor-assisted Power System State Estimator (SPASE) is proposed to monitor and maintain power system performance within known performance metrics.
Abstract: Power system state estimators (ses) have come a long way since the introduction of the concept nearly four decades ago by Fred Schweppe. Over the years, the concept's initial formulation, implementation techniques, computational requirements, data manipulation and storage capabilities, and measurement types have changed significantly. Today, SEs are instrumental in facilitating the security and reliability of power system operation and play an important role in the management of power markets where transactions have to be carefully evaluated for feasibility and determination of real-time prices. One of the most recent developments in SEs has been the availability of synchronized phasor measurements and their introduction into the state estimation process. Synchrophasor-assisted state estimation (SPASE) is changing the way we view and operate the grid. As such, the ability to monitor and maintain SE performance within known performance standards (metrics) is a new practice. Unlike deterministic applications such as power fl ow, the state estimation solution is not deterministic and depends on the statistical characteristics of the measurements as well as the level of certainty of the assumed network model.
TL;DR: In this paper, the authors proposed that India will need to develop renewables, mainly solar and nuclear power, in the coming decades, however, coal will remain the major source of power.
Abstract: As a country that will experience shortages of fossil fuels in the not too distant future, India will need to develop renewables, mainly solar and nuclear power. In the coming decades, however, coal will remain the major source of power. Reducing energy requirements by pushing demand side management is a high-priority option for India. From the viewpoints of both climate change and energy security, these are India's imperatives.
TL;DR: Smart grid is the electric delivery network from electrical generation to the end user that makes use of the latest advances in wireless communication and intelligent information management systems to ameliorate the electric system robustness, reliability, efficiency, and security.
Abstract: Looking at the communication industry, one observes how drastically the communication horizon has changed. From letters to e-mails and SMS, from phone calls to video chat and live conferencing, from phone booths to smart phones: since the digitization of communication, a new era of consumer choice has been inaugurated. The potential exists for similar transformation and opportunity in the provision of electricity, embodied in a concept known as the “smart grid”. Smart grid is the electric delivery network from electrical generation to the end user that makes use of the latest advances in wireless communication and intelligent information management systems to ameliorate the electric system robustness, reliability, efficiency, and security. Like the telecommunications and the genesis of the Internet, technology holds the key to the smart grid and its realization.
TL;DR: Wang et al. as mentioned in this paper reported that wind power installations in China have doubled every year since 2004, and by 2010, China's wind generation capacity of 45 GW ranked first in the world.
Abstract: New wind power installations in China have doubled every year since 2004. By 2010, China's wind generation capacity of 45 GW ranked first in the world. A total of 30 of 31 provinces, municipalities, and autonomous regions have wind farms. (This article does not discuss wind power development in Hong Kong, Macao, and Taiwan.) The Inner Mongolia Autonomous Region leads the other provinces with 14 GW of installed capacity, followed by Gansu, Hebei, and Liaoning. China was also the first country outside of Europe to have offshore wind farms. By the end of 2010, total Chinese offshore wind power capacity was approximately 150 MW.
TL;DR: In Latin America, primary energy demand is projected to grow on average by 1.7% per year and to reach 830 million tons of oil equivalent (mtoe) by 2035, according to the International Energy Agency's 2011 World Energy Outlook as discussed by the authors.
Abstract: In Latin America, primary energy demand is projected to grow on average by 1.7% per year and to reach 830 million tons of oil equivalent (mtoe) by 2035, according to the International Energy Agency's 2011 World Energy Outlook. Demand for renewables in the power generation sector in the region will double over that period, reaching nearly 140 mtoe in 2035. Furthermore, the IEA projects that biofuels use in road transport will increase by more than 4% per year, reaching 1 million barrels per day (mb/d) by 2035, representing around 25% of fuel consumption in the sector. The economic giant in the region, Brazil, will increase its primary energy consumption to 420 mtoe in 2035, representing more than half of the regional total.
TL;DR: In this article, the authors present an application example of online DSA technology in performing near-real-time security assessment of the power system that covers Ireland and Northern Ireland, which is a single synchronous system that has limited HVDC interconnection to Scotland, and the combined maximum and minimum demand of these two systems is approximately 6,800 and 2,500 MW, respectively.
Abstract: This article presents an application example of online DSA technology in performing near-real-time security assessment of the power system that covers Ireland and Northern Ireland. It is a single synchronous system that has limited HVDC interconnection to Scotland. The combined maximum and minimum demand of these two systems is approximately 6,800 and 2,500 MW, respectively. Tripping of the largest generator (440 MW) can result in a frequency fall of more than 0.6 Hz even with a primary fast-acting operating reserve of 75% of the maximum in-feed. The relatively small size of the system also dictates frequency variations wider than those in continental Europe under normal conditions. Generation plant (installed capacity) is mostly thermal, with some 6% of hydro and hydro pumped storage and a 16% wind share that is increasing rapidly. An additional 500-MW HVDC link to the U.K. grid based on voltage source converter (VSC) technology (due for commissioning in 2012) is expected to improve the power system's ability to accommodate wind generation. Increased wind penetration changes the operational characteristics of the power system, primarily due to the unique nature of the wind generation technology described earlier. Increased levels of wind generation introduce new risks and challenges for the transmission system operator.
TL;DR: The journey to the electric grid of 2030 has begun, and there will be plenty of surprises along the way.
Abstract: Due to a variety of recent policy changes and technical innovations, the U.S. electric grid will encounter significant opportunities and challenges over the next several decades. As we have described above, various policy and system-level issues will need to be addressed and new technologies will need to be fully developed and used appropriately for the U.S. grid to evolve along an efficient path with minimal disruption and to ensure electricity rates and levels of reliability remain acceptable. The journey to the electric grid of 2030 has begun, and there will be plenty of surprises along the way. Much can and should be done now to smooth the road ahead.
TL;DR: Fukushima-Daiichi nuclear power plant disaster as discussed by the authors revealed the effects of the failure of the electric supply, pumps, valves, and other components of the nuclear plant infrastructure, and the disaster mobilized the geopolitical world, non-government organizations (NGOs) in general, and environmentalists in particular, as well as national nuclear energy regulatory commissions.
Abstract: The Fukushima-Daiichi nuclear power plant disaster on 11 March 2011, 32 years after the Three Mile Island accident in the United States and 25 years after the Chernobyl meltdown, refocused the world's attention on the potentially catastrophic effects of a nuclear power plant failure. The Japanese disaster revealed the effects of the failure of the electric supply, pumps, valves, and other components of the nuclear plant infrastructure. The six Fukushima-Daiichi nuclear power plant reactors were designed to automatically shut down in case of an earthquake higher than magnitude 6.2 on the Richter scale. This earthquake had an intensity of 9 and, as designed, the safety systems shut down the nuclear fission reactions in the three reactors (out of a total of six) that were in operation. However, the plant design did not have sufficient safeguards to deal with the impact of the tsunami that followed. The disaster mobilized the geopolitical world, non-government organizations (NGOs) in general, and environmentalists in particular, as well as national nuclear energy regulatory commissions. The disaster required the ultimate international authority, the International Atomic Energy Agency (IAEA), to respond rapidly and straightforwardly to the Japanese public and the entire world about the impacts of the nuclear disaster.
TL;DR: This article will attempt to explore multiple definitions of the word security to find some common thread that can help ensure the success of the pursuit of a smarter electrical grid while maintaining security-in all of its various meanings.
Abstract: A critical consideration in the development of smarter electrical grids is to ensure best security practices. Few terms in the smart grid vocabulary, however, are as overworked and overloaded (i.e., assigned multiple definitions) as the word security. Such definitions range all the way from ensuring reliability "keeping the lights on" to protecting the confidentiality of customer information. This article will attempt to explore these multiple definitions and find some common thread that can help ensure the success of the pursuit of a smarter electrical grid while maintaining security-in all of its various meanings.