Showing papers on "Smart grid published in 2004"

Concerns generated by islanding [electric power generation]

Abstract: The purpose of this article is to discuss islanding operation and to provide end-users with items to consider when determining distributed generation plant and equipment design requirements. Islanding is operating an electric generating plant without an external voltage and frequency reference. Operating in parallel is the opposite of islanding. This article attempts to describe the valid concerns that grid operators have regarding distributed generators. Grid computing could offer an inexpensive and efficient means for participant to compete in providing reliable, cheap and sustainable electrical energy supply. With a keen awareness of the issues involved and open communication among the grid operators, generator control system manufacturers, clients and design firms, distributed generators can be operated in islanded mode without negatively impacting the grid and can continue to support facility operations.

Intelligent distributed energy storage system for demand side power management

Abstract: The current invention is an intelligent distributed energy storage system for demand side power management It provides a system that can store electric energy close to the point of use or close to the distributed production for use when demanded by the users These storage nodes can communicate with a central clearing entity to negotiate if the nodes should buy energy for storage, provide energy to the user above a given power level, or sell power back to the grid The function will depend on the amount of energy stored in the node, the cost of the electric energy, the cost of the electric peak power, the price of resold electrical energy and power, plus the local usage

Plug in to grid computing

Abstract: This article discusses the potential benefits of grid computing for future power networks. It is also intended to alert the power system community to the concept of grid computing and to initiate a discussion of its potential applications in future power systems. Much like the Web, the grid can operate over the Internet or any other suitable computer networking technology. Grid computing offers an inexpensive and efficient means for participants to compete (but also cooperate) in providing reliable, cheap, and sustainable electrical energy supply. It also provides a relatively inexpensive new technology allowing the output of embedded generators to be monitored and, when necessary, controlled. Basically, the ability of grid-enabled systems to interact autonomously is vital for small generators where manned operation is likely to be viable.

Wind Farm Power System Model Development

Abstract: —In some areas, wind power has reached a level where it begins to impact grid operation and the stability of local utilities. Utility system operators and engineers now want a better understanding of the impacts of large wind farms on grid stability before they are interconnected to the grid. They need wind farm electrical models that will help them analyze potential grid stability problems. Without the necessary tools and knowledge of large wind power plant behavior, utilities are reluctant to integrate more wind power into the grid. The operating characteristics of a single wind turbine are well known and models to simulate and predict dynamic characteristics under various wind and grid conditions are available. However, models that can simulate and predict the behavior of large wind power plants with hundreds of wind turbines and their impact on the power system operations have yet to be developed. In this paper, the model development for a large wind farm will be presented. Grid stability during electrical transients depends on generators providing voltage stability. Wind farm dynamic behavior and contribution to stability during transmission system faults will be examined.

Wireless Grids: Approaches, Architectures and Technical Challenges

Abstract: Grid computing and grid topologies are attracting a growing amount of attention. Originating as a concept for sharing computing resources among wired participants, the grid concept is gradually been extended into the wireless world. A Wireless Grid is an augmentation of a wired grid that facilitates the exchange of information and the interaction between heterogeneous wireless devices. While similar to the wired grid in terms of its distributed nature, the requirement for standards and protocols, and the need for adequate Quality of Service; a Wireless Grid has to deal with the added complexities of the limited power of the mobile devices, the limited bandwidth, and the increased dynamic nature of the interactions involved. Depending on the nature of the interactions among the constituencies served by the wireless grid, various layouts can be envisaged. The ability of these models to address needs at the enterprise, partner, and service levels is contingent upon the efficient resolution of multiple technical challenges of the grid.

Rethinking over ‘8.14’us-canada blackout after one year

Abstract: The summary, prospect and proposals on the preventive measures, which are published in US authoritative journals and consider the features of power grid, for the blackout occurred in interconnected North America power grid on August 14, last year are briefly introduced According to these comments the inherent structural defects in future domestic plane type structure of 500kV nationwide integrated power grid are pointed out Firstly, the power transmission capability of existing 500kV power networks is insufficient, at present in the South China Power grid the parallel AC/DC mode which ought to support each other becomes the situation of “strong DC network coexisting with weak AC network”; secondly, the plane type high capacity power grid will make the interrupting capability of 500kV breakers quickly increasing; thirdly, for the plane type of nationwide integrated power grid the security defence capability as well as the flexibility of automation system configuration and electricity market operation will meet more difficulties than the pagoda type of power grid structure Therefore, the above-mentioned defects should be vigilant and on guard as early as possible Some proposals on the magnificent prospect of domestic high performance real-time security control system, the difficulties might be met during the research and the stage-by-stage purposes of this research are put forward Besides, it is also pointed out to lead in the coefficient of elasticity for the evaluation of power grid planning to conduct the integrative analysis with the coefficient of elasticity for power industry development, and in this way the goal of “power industry should be developed appropriately in advance and power system nust be developed appropriately in advance”could be realized

Wide-area real time dynamic security monitoring system of north china power grid

Abstract: The full view of power system dynamic processes can be supervised by wide-area real time dynamic monitoring system (WAMS) based on synchronous phasor measurement (SPM) technology. Meanwhile, the recorded data of the power system disturbance accidents is helpful to the off-line verification of the model and parameters of simulation system. Based on the development of real-time dynamic monitoring system for North China Power Grid, the architecture, main functions and features of the monitoring system are described in detail. The first stage of this monitoring system consists of the master-station located at the dispatching center of North China Power Grid and the sub-stations installed in seven key power plants and substations; the connection among the sub-stations is implemented by dispatching data network. The practical application of this WAMS in North China Power Grid is presented through the artificial large disturbance test for three-phase short circuit occurred in Northeast China Power Grid.

/spl Phi/grid: grid computing infrastructure for power systems

Abstract: This paper presents a framework of PI Grid system, a Grid computing platform for power systems, which shows how grid technologies and high performance computing can be efficiently used for power system applications A prototype system is built to enable the distributed unified power flow calculation in this grid computing environment

Revolution in the distribution (use of the technology power line communication in the transmission of data, voice and images)

Abstract: Technology development caused a real revolution inside the electric power distribution industry The significant news came from the solution knows as power line communication (PLC) or broadband over power line communication (BPL) as solution for data, voice and images transmission transported by the electric grid This new technology which is already in Brazil in several commercial trials, will uprising all services from electric power distribution companies thanks to a data transmission that will allow services, such as remote reader, automated motorized switches in medium tension, connection and reconnection services, grid supervision, load management, halt frauds, etc Also this technology permit services as high speed Ethernet, digital telephony, videoconference and video surveillance, and residential automation, adding value to the infrastructure electric grid In this way one of the most attractive business will be the additional revenue that came from multimedia services, which will produce resources to build up the own distribution companies services This paper will address to the technology status, will present several business trials geared by AES Eletropaulo in your electric grid and its results as well as its regulatory framework in Brazil

Analysis on operational problems in south china ac-dc hybrid power grid

Abstract: The South China power grid is the first long-distance and huge capacity power grid with AC and DC power networks in parallel in China. Here, the general situation of South China power grid is introduced and the main problems in this grid such as weak damping and inadequate dynamic voltage supporting ability, etc., are analyzed. On the basis of analyzing the related technological strategy existing in South China power grid, the ways and the measures to solve these problems are researched and the prospect of future works are given.

Grid computing: the next network challenge!

Abstract: Contact details for authors: Bruno Volckaert Department of Information Technology (INTEC) Ghent University, Sint-Pietersnieuwstraat 41, B-9000 Gent (Belgium) Tel: +32 (0) 9 264 9964 Email: Bruno.Volckaert@intec.UGent.be For the past five years, grid computing has been a very hot and fruitful research theme resulting now in the deployment of the first operational grid systems. The main motivation for this new computing paradigm lies in the observation that the demand for computational and storage resources is ever growing while on the other hand vast resources remain underused. The grid paradigm aims at solving this mismatch by offering its users computational and storage resources transparently, making abstraction of the exact geographic location of the physical resource (this approach has appealing similarities to the power grid, hence the term grid computing). Despite the current deployment of operational grid systems, important challenges still lie ahead. New applications, opening the grid also for commercial exploitation, impose new requirements in terms of, for example, security, scaling behaviour, quality of service and robustness. In particular the geographic spread of grid users in combination with these new requirements will certainly have drastic consequences for the communication infrastructure. This paper discusses an overview of current grid systems, application taxonomy and emerging trends. The implications for the network are analysed, taking current grid deployments as a starting point. The importance of co-management of computational/ storage and network resources is illustrated.

Grid Network Monitoring in the European Datagrid Project

Abstract: A Grid Network monitoring and performance measurement infrastructure is a key component of a large-scale Grid. Requirements for network monitoring with respect to Grid operations as well as performance characteristics and their relevance to Grid context have to be carefully identified before realizing such a system. In this paper we analyze the main issues raised by the design, development, integration in a Grid middleware and deployment of a network monitoring infrastructure in a real Grid environment. Then we present the details of the architecture we proposed in the context of the European DataGRID project and the MapCenter tool we developed to vizualize the Grid status in real time and to give access to our measurement infrastructure.

Electrical substation reliability evaluation with emphasis on evolving interdependence on communication infrastructure

Abstract: This study developed a probabilistic methodology for assessment of the reliability and security of electrical energy distribution networks. This included consideration of the future grid system, which will rely heavily on the existing digitally based communication infrastructure for monitoring and protection. Event tree and fault tree methods were utilized. The approach extensively modeled the types of faults that a grid could potentially experience, the response of the grid, and the specific design of the protection schemes. We demonstrated the methods by applying it to a small subsection of a hypothetical grid based on an existing electrical grid system of a metropolitan area. The results showed that for a typical design that relies on communication network for protection, the communication network reliability could contribute significantly to the frequency of loss of electrical power. The reliability of the communication network could become a more important contributor to the electrical grid reliability as the utilization of the communication network significantly increases in the near future to support "smart" transmission and/or distributed generation.

Challenges and Opportunities in Grid Performability

Abstract: Grid computing offers many scientific and commercial benefits, but also many technical and organisational challenges. This has led to many research areas in traditional distributed systems directing their efforts on to grid systems. Amongst the challenges for grid computing is the need to provide reliable quality of service to end users. This paper seeks to identify some of the challenges and opportunities that exist in the field of grid computing relating to system performance and dependability. These challenges are extensive and vary considerably as to the amount of effort that they are currently attracting.

/spl Pi/ grid: grid computing infrastructure for power systems

Abstract: In this paper, a framework of the Grid computing platform for power systems with the name of '/spl Pi/-grid' is presented. Then, the architecture of the /spl Pi/-grid is introduced from both the view of its real physical structure and the view of the middleware layers. Further more, the power system applications that can be built on this platform for real power system use are outlined. As the first milestone, a prototype system of the /spl Pi/-grid is built up, which is designed to solve the distributed unified power flow problem in the grid computing environment.

Survivable Systems Analysis of the North American Power Grid Communications Infrastructure.

Abstract: The modern electric power grid is a complex interconnected network of independent physical and electronic devices that utilize myriad technologies for communication between other devices and with centralized control centers. These technologies may be compromised by malicious parties which may, in turn, lead to degraded performance or a failure of the communications infrastructure, ultimately resulting in loss of power grid transmission and/or distribution capabilities. This paper presents a Survivable Systems Analysis (SSA) of the North American power grid communications infrastructure. The SSA is used to identify general classes of inherent and emergent weaknesses within the North American electric power grid and propose appropriate means to mediate them. The analytic technique is applicable to any national or regional power grid, and can be generalized to most widearea, complex, real-time control infrastructures such as transportation systems, natural gas distribution, and oil pipeline transmission systems.

Utilities Look to the Skies for Monitoring the Power Grid

Abstract: Early next year, power utilities across the United States could be looking to the skies to help them collect meter information about electricity use They'll use satellites to acquire data on a near real-time basis so they can provide users with accurate usage data and model and predict power grid status more accurately

Power system operation control should be in step with its expansion -a brief analysis of large scope blackout in interconnected northeast america power grid

Abstract: According to the interim report and final report of the large scope blackout occurred on Aug. 14, 2003 in Interconnected Northeast America Power Grid, the reasons of this blackout, such as unbefitting interconnection among different voltage grades, the shortage of reactive power in some power networks in the grid, failures of power system automation devices, deficient sharing of power system operation information, lacking unified command under emergency or at the beginning and extension of the faults etc., are analyzed. Hence, some suggestions on the power grids interconnection in China, which is available for reference, e.g., proper interconnection among power gird with same voltage grade, the reactive power should be balanced at local power network while the active power is supplied from other power networks, power system automation should be high-reliable, to carry out unified dispatching and hierarchical control to improve the power system security, etc., are proposed.

Analysis including reliability, income and cost for power systems

Abstract: This paper presents a mathematical method for analysis of reliability and associated cost regarding electrical power grids and similar systems. The reliability analysis is based on Markov models established by means of unit models, which is an efficient method for analysis of large systems. General principles concerning application of the method are presented and illustrated by an example from a local power grid in Norway

Sun's grid model

Abstract: The grid creates a universal source of computing power. Grid opportunity drivers are commodity servers with improving performance, high speed networking enabling distributed computing, Linux OS/ Solaris X86, grid resource management software maturing. Grid are accessed and managed through grid software like N1 grid engine.

Grid computing and its application in power systems

Abstract: This paper introduces the origination, definition, function and performance of the grid computing technology. Probable applications of grid computing to power system monitoring and control are depicted in consideration of the operation requirement of real power systems. Basic characteristics of computing grid of the future power system are also predicted.

Adequacy evaluation for south china electric power grid in 2005

Abstract: In 2005, South China Electric Power Grid will become the large-scale AC/DC power system, which includes “Five-AC/Three-DC” transmission lines to transfer power from West China to East China. The reliability adequacy evaluation is studied based on the 2005’s planning data of South China Electric Power Grid, which includes 1437 components. The system state sample results show that the often occurred multiple generator faults will be the major trouble in the power grid that time, so it is necessary to provide enough fault reserve to improve the reliability. A series of reliability indices are proposed. The system reliability indices, the load bus reliability indices and the area reliability indices are calculated. The weaknesses of the system are pointed out and the suggestions to improve the reliability level of the power grid are given. The evaluation results are available for reference in the planning and operation of the actual power grid.

Power grid planning under electricity market

Abstract: The establishment of a competitive electricity market in China sets great challenges to power grid planning. On the one hand, it is confronted with many uncertainties including load development, power source construction, power flow variation, etc; on the other hand, it has to satisfy consumers' demand for an economic, safe, flexible and open power grid. In this paper, it is expounded that power grid planners should lay emphasis on important issues including load forecasting and generation planning, analyze various schemes for network frame, diversify investors for power grid and strengthen readjustment to the planning.

Requirements and design of a dynamic Grid networking layer

Abstract: We address the requirements and design of bandwidth on demand networks in the context of Grid services. Regardless of the deployment scenario for Grid services (e.g., commercial or research), there is a need for efficient use of network facilities and a need to meet the performance requirements of the Grid services users. We present quantitative analysis showing how these needs can be met.

Discussion on stability control of Fujian Power Grid after being interconnected to East China Power Grid

Abstract: The influence of grid interconnection between Fujian and East China on the security and stability of Fujian Power Grid was analyzed, as well as the new features of the grid stability Aiming at the security and stability problems of Jujian Power Grid after being interconnected to East China Power Grid, the relevant security and stability measures were put forward The setting-up plan of the third line of defence for Fujian Power Grid after being interconnected and the existing problems were analyzed and suggestions were put forward on the structure and planning of Fujian Power Grid