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Controle e integração de centrais eólicas à rede elétrica com geradores de indução duplamente alimentados. ; Control and integration of wind farms to the power grid using doubly fed induction generators.

Silva, Kleber Freire da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 14/03/2006 PT
Relevância na Pesquisa
56.37%
Esta Tese trata do controle e integração de centrais eólicas à rede elétrica interligada, utilizando-se geradores de indução duplamente alimentados (GIDE). O objetivo principal da Tese foi desenvolver estratégias de controle discreto para o sistema de geração eólica, de forma a reduzir os impactos na qualidade da energia gerada, em função dos diversos regimes e transitórios de vento, que podem ocorrer no sítio eólico. Para o projeto do sistema de controle dos geradores foi adotada a técnica do controle vetorial, de forma a desacoplar o controle do fluxo das potências ativa e reativa entre o gerador e a rede elétrica. Visando caracterizar os diversos modos de operação do GIDE, com velocidades acima e abaixo da síncrona, foi desenvolvido um estudo de regime permanente do gerador, obtendo-se os limites de correntes, tensões e demais grandezas elétricas e mecânicas, para uma determinada faixa de velocidade. As principais estratégias de controle atualmente utilizadas pelos fabricantes de turbinas eólicas foram analisadas, destacando-se os aspectos da eficiência energética do conjunto turbina-gerador e da qualidade da energia. O projeto das malhas de controle dos conversores estáticos conectados ao circuito do rotor foi desenvolvido utilizando a técnica de controle discreto...

Contribuição à análise do controle de potências ativa e reativa de um gerador de indução com rotor bobinado conectado a uma rede elétrica com tensão distorcida : A contribution to the active and reactive power control analysis of a wound-rotor induction generator connected to a electric grid with distorted voltage; A contribution to the active and reactive power control analysis of a wound-rotor induction generator connected to a electric grid with distorted voltage

Ramon Rodrigues de Souza
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/06/2015 PT
Relevância na Pesquisa
46.5%
Esta dissertação é uma contribuição aos estudos relacionados ao controle de potências ativa e reativa de sistemas de geração eólica conectados à rede elétrica. O sistema de geração eólica apresentado neste trabalho utiliza um gerador de indução de rotor bobinado (GIRB), que tem os terminais elétricos dos enrolamentos de estator conectados à rede elétrica e os terminais elétricos dos enrolamentos do rotor ligados a um conversor eletrônico de potência CC/CA (corrente contínua/corrente alternada), que possui a função de controlar as potências ativa e reativa que fluem do estator do gerador elétrico para a rede elétrica. O conversor conectado ao rotor é ligado em cascata a outro conversor eletrônico de potência CA/CC através de um barramento CC com tensão controlada. Por sua vez, este conversor eletrônico de potência CA/CC é conectado a um filtro indutivo que realiza a interface com a rede elétrica. Apresentam-se uma breve visão histórica da utilização da energia eólica, um panorama do atual cenário do setor eólico, fundamentos de energia eólica, vantagens e desvantagens do aproveitamento da energia eólica para geração de eletricidade, a fim de contextualizar sobre a importância da utilização da energia eólica e apresentar as perspectivas de crescimento do setor eólico. Apresenta-se a modelagem matemática do GIRB e do conversor eletrônico de potência conectado à rede elétrica utilizando o conceito de vetores espaciais e as estruturas de controle do sistema de forma detalhada. Expõem-se também as influências das distorções harmônicas na tensão da rede elétrica no sistema de geração eólico estudado. Mostra-se a modelagem de simulações matemáticas dinâmicas do sistema conectado à rede elétrica com tensão distorcida utilizando o software Matlab/Simulink/SimPowerSystems para verificar quais os impactos negativos dos harmônicos de tensão da rede elétrica no sistema investigado. Propõem-se dois métodos para redução de alguns dos impactos causados pela presença de tensões harmônicas de 5ª e 7ª ordens na rede elétrica ao qual o sistema de geração eólico está conectado. Um destes métodos consiste em acrescentar a função de transferência do filtro notch de 6ª ordem em cascata com o controlador PI clássico na malha de controle de corrente do conversor eletrônico de potência que está conectado à rede elétrica. A outra técnica adiciona ao controle de potência ativa e reativa do conversor conectado ao rotor a função de transferência de um compensador ressonante de 6ª ordem. A partir da utilização destas técnicas...

Assessment of a battery charger for electric vehicles with reactive power control

Monteiro, Vítor; Pinto, J. G.; Exposto, Bruno; Gonçalves, Henrique; Ferreira, João C.; Couto, Carlos; Afonso, João L.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em 25/10/2012 ENG
Relevância na Pesquisa
46.47%
Batteries of Electric Vehicles (EVs) and Plug-in Hybrid Electric Vehicles (PHEVs) have a large potential not only to provide energy for the locomotion of these vehicles, but also to interact, in dynamic way, with the power grid. Thereby, through the energy stored in the batteries, these vehicles can be used to regulate the active and the reactive power, as local Energy Storage Systems. This way, EVs can contribute to help the power grid to regulate the active and reactive power flow in order to stabilize the production and consumption of energy. For this propose should be defined usage profiles, controlled by a collaborative broker, taking into account the requirements of the power grid and the conveniences of the vehicle user. Besides, the interface between the power grid and the EVs, instead of using typical power converters that only work on unidirectional mode, need to use bidirectional power converters to charge the batteries (G2V - Grid-to-Vehicle mode) and to deliver part of the stored energy in the batteries back to the power grid (V2G - Vehicle-to-Grid mode). With the bidirectional power converter topology presented in this paper, the consumed current is sinusoidal and it is possible to regulate the power factor to control the reactive power...

A wireless sensor and actuator network for improving the electrical power grid dependability

Grilo, António; Casaca, Augusto; Pereira, Paulo; Buttyan, Levente; Gonçalves, José; Fortunato, Carlos
Fonte: Repositório Comum de Portugal Publicador: Repositório Comum de Portugal
Tipo: Conferência ou Objeto de Conferência
Publicado em //2012 ENG
Relevância na Pesquisa
66.26%
This paper presents an overview of a Wireless Sensor and Actuator Network (WSAN) used to monitor an electrical power grid distribution infrastructure. The WSAN employs appropriate sensors to monitor key grid components, integrating both safety and security services, which improve the grid distribution dependability. The supported applications include, among others, video surveillance of remote secondary substations, which imposes special requirements from the point of view of quality of service and reliability. The paper presents the hardware and software architecture of the system together with performance results.

High performance power delivery for nanoscale integrated circuits

Köse, Selçuk ; Friedman, Eby G.
Fonte: University of Rochester Publicador: University of Rochester
Tipo: Tese de Doutorado Formato: Number of Pages:xxiii, 240 leaves; Illustrations:ill. (some col.)
ENG
Relevância na Pesquisa
56.23%
Thesis (Ph. D.)--University of Rochester. Dept. of Electrical and Computer Engineering, 2012.; A critical challenge in high performance nanoscale integrated circuits is high quality power delivery. The efficient generation and distribution of multiple on-chip power supply voltages require fundamental changes to the power delivery process to provide increased current in next generation nanoscale integrated circuits. Four primary components are required to realize an efficient power delivery system: (a) ultra-small voltage converters to generate power close to the load, (b) accurate models to characterize the individual power components, (c) efficient algorithms to analyze the quality of the power delivered to the load circuits, and (d) a co-design methodology to simultaneously determine the optimal location of the on-chip power supplies and decoupling capacitors. In this dissertation, a hybrid combination of a switching and low-dropout (LDO) regulator as a point-of-load power supply for next generation heterogeneous systems is proposed. The area of this circuit is significantly smaller than the area of conventional voltage regulators, while maintaining high current efficiency. The proposed circuit provides a means for distributing multiple local power supplies across an integrated circuit. Another important challenge in the realization of effective power delivery systems is the analysis of this highly complicated structure where individual voltage fluctuations at millions of nodes need to be efficiently determined. Closed-form expressions for the effective resistance between circuit components have been developed. This effective resistance model is utilized in the development of a power grid analysis algorithm to compute the node voltages without requiring any iterations. This algorithm drastically improves computational complexity since the iterative procedures to determine IR drop and L di/dt noise are no longer needed. With the introduction of ultra-small on-chip voltage regulators...

AN EFFICIENT DEMAND-SIDE LOAD SHEDDING ALGORITHM IN SMART GRID

Li, Yang
Fonte: Quens University Publicador: Quens University
Tipo: Project
EN
Relevância na Pesquisa
46.45%
Rapid advances in the smart grid technology are making it possible to tackle a lot of problems in the aged power systems. High-speed data acquisition system, high-voltage power electronic equipment, advanced utility and customer interaction technologies, as well as distributed renewable generation are enabling the revolution in the electric power generation, delivery and distribution. Through the implementation of ubiquitous metering and communication networks, the customers would no longer be a passive receiver of the electrical energy, but instead, an active participant in the power system and electricity market. They can not only sell their own energy to the utility, but also take part in the emergency restoration in the power grid. Nonetheless, some technical barriers are encountered during this revolution, such as difficulties in integrating home automation, smart metering, customer interaction and power system operation into the whole system. This thesis proposes a customer involved load shedding algorithm for both the power system frequency control and the micro-grid islanding. This new algorithm possesses the features of centralized load control and distributed load control, which fully utilizes the advantages of hierarchical communication networks along with the home automation. The proposed algorithm considers the reliability of the power grid as well as the comfort of the electricity users. In the power distribution system...

Investigation and Research of China Power Social Universal Services

North China Electric Power University
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
56.33%
The investigation conducted by this project concernt China power social universal services include: the investigation on the actuality of the domestic power social universal services or on the other industries and the research and study on abroad services. Through research of the domestic power social universal service, we could realize the actuality of the domestic power social universal services, hold the scale of the requirement, the characteristics of the region, and also the existing problems and obstacles of the universal service, furthermore, calculate the amount of capital that power social universal services needed; then draw the successful experience of domestic and foreign services to make suggestions on the policy, regulatory measures and implementation of programs which are adapt to the development of China power social universal service.

International Experience with Open Access to Power Grids : Synthesis Report

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
46.47%
Reliable and affordable supply of electricity is a key driver of economic growth. In recent decades, many developing and emerging economies have embarked on efforts to enhance the efficiency of their electricity markets. The quest for efficiency often involves structural reforms such as unbundling and other measures designed to support greater competition in the power sector. Open Access (OA) to Transmission and Distribution (T&D) grids by market participants is an essential element in this reform process. The study has proceeded on two tracks: one based on empirical findings from specific country cases, and a generic one synthesizing the emerging global issues in OA. Reports for the country studies have been prepared for Brazil, Peru, Turkey, India, and the Philippines. In addition, a global review of the experience in a broader group of countries, both developed and developing, has been undertaken. Overall, the study has taken a broad approach to defining OA - going well beyond the minimalist notion of simply guaranteeing legal access to the grid for generators and wholesale buyers.

Power for All : Electricity Access Challenge in India

Banerjee, Sudeshna Ghosh; Barnes, Douglas; Singh, Bipul; Mayer, Kristy; Samad, Hussain
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
EN_US
Relevância na Pesquisa
46.47%
India has led the developing world in addressing rural energy problems. By late 2012, the national electricity grid had reached 92 percent of India s rural villages, about 880 million people. In more remote areas and those with geographically difficult terrain, where grid extension is not economically viable, off-grid solutions using renewable-energy sources for electricity generation and distribution have been promoted. The positive results of the country s rural energy policies and institutions have contributed greatly to reducing the number of people globally who remain without electricity access. Yet, owing mainly to its large population, India has by far the world s largest number of households without electricity. More than one-quarter of its population or about 311 million people, the vast majority of whom live in poorer rural areas, still lack an electricity connection; less than half of all households in the poorest income group have electricity. Among households with electricity service, hundreds of millions lack reliable power supply.

An enhanced implementation of models for electric power grid interdiction

Carnal, David D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 43 p. : col. ill. ;
Relevância na Pesquisa
56.11%
This thesis evaluates the ability of the Xpress-MP software package to solve complex, iterative mathematicalprogramming problems. The impetus is the need to improve solution times for the VEGA software package, which identifies vulnerabilities to terrorist attacks in electric power grids. VEGA employs an iterative, optimizing heuristic, which may need to solve hundreds of related linear programs. This heuristic has been implemented in GAMS (General Algebraic Modeling System), whose inefficiencies in data handling and model generation mean that a modest, 50-iteration solution of a real-world problem can require over five hours to run. This slowness defeats VEGA's ultimate purpose, evaluating vulnerability-reducing structural improvements to a power grid. We demonstrate that Xpress-MP can reduce run times by 60%-85% because of its more efficient data handling, faster model generation, and the ability, lacking entirely in GAMS, to solve related models without regenerating each from scratch. Xpress-MP's modeling language, Mosel, encompasses a full-featured procedural language, also lacking in GAMS. This language enables a simpler, more modular and more maintainable implementation. We also demonstrate the value of VEGA's optimizing heuristic by comparing it to rule-based heuristics rules adapted from the literature. The optimizing heuristic is much more powerful.

Policy and Governance Framework for Off-grid Rural Electrification with Renewable Energy Sources

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Energy Study; Economic & Sector Work
ENGLISH
Relevância na Pesquisa
46.52%
The objective of the study was to develop an adequate policy and governance framework for off- grid rural electrification by: assessing the effectiveness and key socio-economic factors and governance structures in present off-grid electricity supply schemes; and exploring and testing sustainable decentralized service-delivery models for future large-scale off-grid rural electrification in Pakistan. This study has attempted to develop a policy and governance framework for implementing sustainable large-scale off-grid rural electrification in Pakistan. This was done by assessing the effectiveness of existing policy, governance, and institutional frameworks in actual implementation of off-grid supply (OS) projects in the country; examining regional and global models for off-grid supply which have worked; and exploring which combination of these experiences might work to scale-up access in Pakistan to reach the roughly 7,000 villages which are not likely to be supplied by grid electricity in the near future. Pakistan has in place...

Surge in Solar-Powered Homes : Experience in Off-Grid Rural Bangladesh

Khandker, Shahidur R.; Samad, Hussain A.; Sadeque, Zubair K.M.; Asaduzzaman, Mohammed; Yunus, Mohammad; Haque, A.K. Enamul
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH
Relevância na Pesquisa
46.46%
Bangladesh has made remarkable progress in raising living standards and reducing poverty, particularly in previously lagging regions. Rapid solar home system (SHS) expansion in Bangladesh to some 3 million rural households by early 2014 has drawn the attention of donors and governments of other countries. The book s broad aim is twofold: (a) to assess the welfare impact of SHS on households, and (b) to evaluate the present institutional structure and financing mechanisms in place, noting that households want cheaper systems and good quality service while suppliers require a reasonable market-based profit to stay in business. The study entailed an intensive empirical investigation based on both primary and secondary data. The primary data consisted mainly of a large-scale, nationally representative household survey with appropriate geographic spread. Conducted in 2012 by the Bangladesh Institute of Development Studies (BIDS) and assisted by the World Bank, the household survey was designed to examine SHS benefits and costs. The book addresses a number of research issues...

Practical Guidance for Defining a Smart Grid Modernization Strategy : The Case of Distribution

Madrigal, Marcelino; Uluski, Robert
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Tipo: Publications & Research :: Publication
ENGLISH; EN_US
Relevância na Pesquisa
56.55%
This report provides some practical guidance on how utilities can define their own smart grid vision, identify priorities, and structure investment plans. While most of these strategic aspects apply to any area of the electricity grid, the document focuses on the segment of distribution. The guidance includes key building blocks that are needed to modernize the distribution grid and provides examples of grid modernization projects. Potential benefits that can be achieved (in monetary terms) for a given investment range are also discussed. The concept of the smart grid is relevant to any grid regardless of its stage of development. What varies are the magnitude and type of the incremental steps toward modernization that will be required to achieve a specific smart grid vision. Importantly, a utility that is at a relatively low level of grid modernization may leap frog one or more levels of modernization to achieve some of the benefits offered by the highest levels of grid modernization. Smart grids impact electric distribution systems significantly and sometimes more than any other part of the electric power grid. In developing countries...

Lao PDR - Power to the People : Twenty Years of National Electrification

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Energy Study; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
46.47%
This report documents the Lao People's Democratic Republic's success story in rapid national electrification integrated within a broader strategy of national and rural development. In fifteen years (1995-2009), electricity access more than quadrupled, from about 15 percent in 1995 to 69 percent in 2009 -- and the program is on track to achieve the government's target of 70 percent national coverage by 2010 year-end. This expanded electricity access resulted in over 700,000 household connections by 2009 year-end, from about 120,000 households connected in 1995. The government of Lao PDR (GoL) has pursued a pragmatic and purposeful approach. Further, a series of government policy initiatives helped steer the rapid liberalization and modernization of the national economy, as a consequence of which the economy has grown at an average annual rate of 6.5 percent since 2001. The key to the successful implementation of the national electrification program in Lao PDR has been its institutional model of grid extension and rollout driven by the national electricity utility...

AN EFFICIENT DEMAND-SIDE LOAD SHEDDING ALGORITHM IN SMART GRID

LI, YANG
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
46.45%
Rapid advances in the smart grid technology are making it possible to tackle a lot of problems in the aged power systems. High-speed data acquisition system, high-voltage power electronic equipment, advanced utility and customer interaction technologies, as well as distributed renewable generation are enabling the revolution in the electric power generation, delivery and distribution. Through the implementation of ubiquitous metering and communication networks, the customers would no longer be a passive receiver of the electrical energy, but instead, an active participant in the power system and electricity market. They can not only sell their own energy to the utility, but also take part in the emergency restoration in the power grid. Nonetheless, some technical barriers are encountered during this revolution, such as difficulties in integrating home automation, smart metering, customer interaction and power system operation into the whole system. This thesis proposes a customer involved load shedding algorithm for both the power system frequency control and the micro-grid islanding. This new algorithm possesses the features of centralized load control and distributed load control, which fully utilizes the advantages of hierarchical communication networks along with the home automation. The proposed algorithm considers the reliability of the power grid as well as the comfort of the electricity users. In the power distribution system...

Modelagem matemática e implementação computacional no ATP de um sistema solar fotovoltaico conectado a rede de baixa tensão; Mathematical modeling and computational implementation in ATP of photovoltaic solar system connected to low voltage power grid

Cunha, Guilherme Henrique Bernardes
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
POR
Relevância na Pesquisa
56.23%
O aumento da demanda de energia, a possibilidade de redução do suprimento de combustíveis convencionais e a crescente preocupação com a preservação do meio ambiente têm levado a várias pesquisas e desenvolvimento de fontes alternativas de energia que sejam limpas, renováveis e com menor impacto ambiental. Dentre as diversas fontes alternativas de energia, a solar fotovoltaica tem sido considerada uma excelente opção já que é livre, abundante, limpa e distribuída. A energia solar incidente na superfície da Terra é estimada em cerca de dez mil vezes a energia total consumida no mundo. Mesmo com todas as vantagens apresentadas pela geração de energia por meio do uso de painéis fotovoltaicos, a eficiência da conversão de energia é atualmente ainda baixa e com custo inicial de implantação elevado. Assim, é imprescindível o uso de técnicas para extração da máxima potência destes painéis para aumentar a eficiência de operação do sistema. Este trabalho visa apresentar estudos de um sistema fotovoltaico completo conectado à rede elétrica de baixa tensão, compreendendo o painel solar, um conversor elevador de tensão, seu correspondente controle de rastreamento de máxima potência, o inversor de tensão com seu controle...

Design of an electrical power assist kit for manual wheelchair under the conditions of developing countries

Mej??a Guti??rrez, Ricardo; Zuluaga Holgu??n, Daniel
Fonte: Grupo de Investigaci??n en Ingenier??a de Dise??o - GRID; Design Engineering Research Group - GRID; Escuela de Ingenier??a Publicador: Grupo de Investigaci??n en Ingenier??a de Dise??o - GRID; Design Engineering Research Group - GRID; Escuela de Ingenier??a
Tipo: conferenceObject; Documento de conferencia; publishedVersion
ENG
Relevância na Pesquisa
56.17%
Electric mobility has become an important issue worldwide; proof of this is that all the transportation areas are tending towards a green approach for their business by using renewable energies -- In parallel form, mobility for disabled people is a global concern right now, specifically how to improve the independency and raise the standard of living of people in this situation -- Electric mobility solutions have provided an important advance in the independency of patients -- However, as occurs with emerging technologies the price is quite high, especially for developing countries such as Colombia -- This work presents the design of an electric power kit for manual wheelchair, with the aim of making it adaptable for different wheelchair brands available in the Colombian market

Scaling Up Access to Electricity; Emerging Best Practices for Mini-Grid Regulation

Greacen, Chris; Nsom, Stephanie; Rysankova, Dana
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Journal Article; Publications & Research :: Brief; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
46.5%
This brief will focus on enabling regulations for mini-grids, providing an overview of key issues, options, and good practices. While appropriate regulations are not all that is needed to spur mini-grid development, is usually one of the first obstacles that potential developers face and therefore the most urgent issue for governments. The authors draw on a case study of Tanzania, a pioneer in setting an enabling and light-handed regulatory framework for mini-grids. Given the urgency of leveraging private sector investments for reaching the universal access targets of the international sustainable energy for all projects, the authors also focus on regulatory issues relevant to private sector entrepreneurs and investors. Mini-grid entrepreneurs need to know that their investment of time and money will have a reasonable chance not just of being repaid but also of returning a profit. A clear and credible regulatory framework that makes and enforces fair and efficient decisions in a timely manner helps entrepreneurs make informed investment decisions. The key characteristics of such a framework...

Multifunctional converter to interface renewable energy sources and electric vehicles with the power grid in smart grids context

Monteiro, Vítor; Pinto, J. G.; Exposto, Bruno Fernandes; Pedrosa, Delfim; Afonso, João L.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em /06/2015 ENG
Relevância na Pesquisa
56.5%
This paper proposes a multifunctional converter to interface renewable energy sources (e.g., solar photovoltaic panels) and electric vehicles (EVs) with the power grid in smart grids context. This multifunctional converter allows deliver energy from the solar photovoltaic panels to an EV or to the power grid, and exchange energy in bidirectional mode between the EV and the power grid. Using this multifunctional converter are not required multiple conversion stages, as occurs with the traditional solutions, where are necessary two power converters to integrate the solar photovoltaic system in the power grid and also two power converters to integrate an off-board EV battery charger in the power grid (dc-dc and dc-ac power converters in both cases). Taking into account that the energy provided (or delivered) from the power grid in each moment is function of the EV operation mode and also of the energy produced from the solar photovoltaic system, it is possible to define operation strategies and control algorithms in order to increase the energy efficiency of the global system and to improve the power quality of the electrical system. The proposed multifunctional converter allows the operation in four distinct cases: (a) Transfer of energy from the solar photovoltaic system to the power grid; (b) Transfer of energy from the solar photovoltaic system and from the EV to the power grid; (c) Transfer of energy from the solar photovoltaic system to the EV or to the power grid; (d) Transfer of energy between the EV and the power grid. Along the paper are described the system architecture and the control algorithms...

A network approach for power grid robustness against cascading failures

Wang, Xiangrong; Koç, Yakup; Kooij, Robert E.; Van Mieghem, Piet
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/05/2015
Relevância na Pesquisa
46.46%
Cascading failures are one of the main reasons for blackouts in electrical power grids. Stable power supply requires a robust design of the power grid topology. Currently, the impact of the grid structure on the grid robustness is mainly assessed by purely topological metrics, that fail to capture the fundamental properties of the electrical power grids such as power flow allocation according to Kirchhoff's laws. This paper deploys the effective graph resistance as a metric to relate the topology of a grid to its robustness against cascading failures. Specifically, the effective graph resistance is deployed as a metric for network expansions (by means of transmission line additions) of an existing power grid. Four strategies based on network properties are investigated to optimize the effective graph resistance, accordingly to improve the robustness, of a given power grid at a low computational complexity. Experimental results suggest the existence of Braess's paradox in power grids: bringing an additional line into the system occasionally results in decrease of the grid robustness. This paper further investigates the impact of the topology on the Braess's paradox, and identifies specific sub-structures whose existence results in Braess's paradox. Careful assessment of the design and expansion choices of grid topologies incorporating the insights provided by this paper optimizes the robustness of a power grid...