Electrical Distribution Networks E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 568

Veröffentlichungsjahr: 2013

Beschreibung

This book describes the fundamental aspects of the new generation of electrical distribution grids, taking as its starting point the opportunities that exist for restructuring existing infrastructure. It emphasizes the incorporation of renewable energy sources into the distribution grid and the need for a technological evolution towards the implementation of smartgrids.
The book is organized into two parts: the first part analyzes the integration of distributed energy sources into the distribution grid and the impact of these sources on grid operation. After a general description of the general characteristics of distribution grids and renewable energy sources, it then analyzes the economics of electrical energy distribution networks and presents the impact of these sources on grid operation. The second part of the book then analyzes the various functions which allow for safe operation of the grid and realization of the path towards real world application of smartgrids.

Leseprobe

Table of Contents

Preface

Chapter 1: The Electrical Distribution Network: From Heritage to Innovation

1.1. Introduction

1.2. The new power system paradigm

1.3. Structure and characteristics of current distribution systems

1.4. Consumption

1.5. Transmission and distribution systems operators

1.6. Future challenges for the distribution system

1.7. The link between investment and quality

1.8. Financing mechanisms and investment actors of distribution systems

1.9. Conclusion

1.10. Glossary

1.11. Bibliography

Chapter 2: Characteristics of Distribution Networks

2.1. Part 1: the French network

2.2. The North American network

2.3. Bibliography

Chapter 3: Overview of Decentralized Means of Production

3.1. Introduction

3.2. Deregulation

3.3. Emergent means of production

3.4. Conclusion: a challenge and a development opportunity for mains power

3.5. Bibliography

Chapter 4: Connection to the Decentralized Production Network: Regulatory and Economic Aspects

4.1. Introduction

4.2. European policies and growth dynamics of REn

4.3. Incentive policies for the deployment of renewable energies

4.4. Integration and connection of new renewable energy producers to the network

4.5. The insertion of renewable energies into the electrical market

4.6. Bibliography

Chapter 5: Impacts of Distributed Generation on the Electrical Network

5.1. Introduction

5.2. Impact of distributed generation on electrical parameters

5.3. Impacts on the design, planning and exploitation

5.4. Impacts on network equipment

5.5. Bibliography

Chapter 6: Photovoltaic Systems Connected to the Network

6.1. Introduction to grid-connected PV production

6.2. Structure of photovoltaic inverters

6.3. Control/command of the grid side converter

6.4. Anti-islanding protection of PV systems

6.5. Impact on the voltage and harmonics of grid connected PV systems

6.6. Impact on the voltage [TRA 09]

6.7. Impact on voltage unbalance

6.8. Conclusion

6.9. Bibliography

Chapter 7: Voltage Control in Distribution Systems with Dispersed Generation

7.1. Introduction: problems of voltage control

7.2. Voltage control in today’s distribution systems

7.3. Voltage control in distribution systems with DG

7.4. Conclusion

7.5. Bibliography

Chapter 8: Grid Integration of Wind Turbine Systems and their Ancillary Services Participation

8.1. Wind energy: context

8.2. Integration of wind energy in electrical systems

8.3. Grid code requirements and wind farms

8.4. Wind turbines: principles and modeling aspect

8.5. Study of mixed wind farm integration in an islanded grid

8.6. Bibliography

8.7. Manufacturers websites

8.8. List of symbols

Chapter 9: Reliability of Distribution Systems with Dispersed Generation

9.1. New considerations and challenges for the reliability of distribution systems

9.2. Basic concepts of electrical network reliability

9.3. Objectives and use of probabilistic reliability studies…

9.4. Basic concepts of Monte Carlo simulation

9.5. Some results of Monte Carlo method application

9.6. Conclusion

9.7. Bibliography

Chapter 10: Protection, Detection and Isolation of Faults in MV Networks in the Presence of Decentralized Production

10.1. Introduction

10.2. Characteristics of faults in HVA distribution systems

10.3. Functioning of protection in MV networks in the presence of decentralized production

10.4. Detection of faults

10.5. Localization of faults in the presence of decentralized production

10.6. Bibliography

Chapter 11: Load Control in the Management of Distribution Systems

11.1. Objectives of load control for the distributor

11.2. Controlled loads

11.3. Results for real-time control

11.4. Real-time load control with knowledge of houses’ characteristics

11.5. Optimized load control

11.6. Conclusion

11.7. Bibliography

Chapter 12: Power Electronics in the Future Distribution Grid

12.1. Introduction

12.2. New context of distribution systems

12.3. PE systems in the context of existing networks

12.4. Current state of development

12.5. Conclusion

12.6. Bibliography

Chapter 13: Virtual Power Systems for Active Networks

13.1. General context: towards an active network

13.2. Objectives

13.3. Concept of a virtual power plant (project FENIX)

13.4. Other developments: the Alp energy project

13.5. Prospects for virtual power plants on active network

13.6. Bibliography

Chapter 14: Towards Smart Grids

14.1. Introduction

14.2. Definitions of the smart grid

14.3. Objectives addressed by the smart grid concept

14.4. Stakeholders involved in the implementation of the smart grid concept

14.5. Research and scientific aspects of the smart grid

14.6. Conclusion

14.7. Bibliography

List of Authors

Index

We warmly thank Julie Laur for her valuable help formatting the different chapters of this book.

We also warmly thank Jean-Claude Sabonnadière for his valuable contribution in following up and finalizing this book.

First published 2011 in Great Britain and the United States by ISTE Ltd and John Wiley & Sons, Inc.

Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms and licenses issued by the CLA. Enquiries concerning reproduction outside these terms should be sent to the publishers at the undermentioned address:

ISTE LtdJohn Wiley & Sons, Inc.27-37 St George’s Road111 River StreetLondon SW19 4EUHoboken, NJ 07030UKUSAwww.iste.co.ukwww.wiley.com

© ISTE Ltd 2011

The rights of Nouredine Hadjsaïd and Jean-Claude Sabonnadière to be identified as the authors of this work have been asserted by them in accordance with the Copyright, Designs and Patents Act 1988.

Library of Congress Cataloging-in-Publication Data

Electrical distribution networks / edited by Nouredine Hadjsaïd, Jean-Claude Sabonnadière.

p. cm.

Includes bibliographical references and index.

ISBN 978-1-84821-245-9

1. Electric power distribution. I. Hadjsaïd, Nouredine. II. Sabonnadière, Jean-Claude.

TK3001.E385 2011

333.793'2--dc22

2011003205

British Library Cataloguing-in-Publication Data

A CIP record for this book is available from the British Library

ISBN 978-1-84821-245-9

Preface

Less than 10 years ago, a comprehensive book devoted to recent research on distribution systems would have been of limited interest. Indeed for decades the scientific community was only concerned with the development of distribution systems through their expansion and the development of protection equipment and the corresponding switchgears. Thus, the main innovations were primarily related to the equipment, because the structure and functioning of these networks, being simple, did not require special research and development.

In the 1980s, in the UK, and then the US, however, the opening of the energy markets to competition, often called “deregulation”, which was propagated thereafter in Europe and other countries across the world, introduced a new paradigm in the organization of electrical systems. This new paradigm has changed the organization of these systems, notably due to the entrance of new participants and the change in the structures and liabilities following it (the appearance of network operators, providers, producers, etc.).

In many countries, this change of paradigm has occurred simultaneously with the awakening of customers and governments to the worldwide environmental stakes. This has generated an unprecedented passion for renewable energies. The meeting of these two societal phenomena has led to the development of renewable energies: biomass and geothermy have come to supply the heating and electrical networks through cogeneration. At the same time, the fast development of wind and solar power gradually appeared in the form of small power installations, quickly developed, thanks to government aid, into average power installations, described as “wind farms and solar parks”.

The appearance of these new means of production, usually installed on the distribution systems, led the network operators to be concerned with the impact on the latter due to the proliferation of decentralized means of production. Indeed these networks were not intended to host this type of production, whose localization is random and a big part is intermittent and thus not dispatchable.

It is in this context that IDEA (a French consortium for the invention of the electrical distribution of the future) was created between the industrial partners EDF, Schneider Electric Industries and the Polytechnic Institute of Grenoble. The vocation and culture of these partners are complementary. The objective of this group at the very beginning was to analyze the impact of intermittent and random decentralized production on distribution systems.

The culmination of nearly 10 years of innovation and research studies on the various facets of study of the interaction between distribution systems and renewable energy production devices have provided the framework for this book. Professor Nouredine Hadjsaïd, as Director of IDEA, was the most qualified person to ensure the coordination of its writing.

The need to introduce increasingly large quantities of renewable energies into distribution systems led engineers and researchers to imagine new concepts, such as the “virtual power station” or the decentralized voltage regulator, which give these networks the qualities of flexibility, robustness and self-healing. These qualities will enable them to host new generation means, while guaranteeing the security of energy transmission.

These concepts, based on the coordination of the energy structure with information infrastructures, were the premises of the “intelligent energy network”, known as the smart grid. Its repercussion on a worldwide scale shows the urgent need for a comprehensive work on distribution systems.

This book, by the quality and the originality of the contributions, will enable the reader to form a global and exhaustive vision of theoretical and practical tools relating to the concept of the smart grid.

We hope the book gets a particularly enthusiastic reception from the community of researchers and engineers, who in industry as well as in the research field will be involved in the design and erection of the distribution systems of the future.

Jean-Claude SABONNADIÈRE

Emeritus ProfessorNational Polytechnic Institute of Grenoble

April 2011

Chapter 1

The Electrical Distribution Network: From Heritage to Innovation1

1.1. Introduction

An electrical system is made up of three basic segments: generation, network and consumers. For the network segment, two parts have to be distinguished: the transmission and the distribution systems. These systems differ in their topology, voltage levels, size, operations, objectives, etc. Thus, given the deregulation of the power industry, each segment is characterized by specific actors.

Figure 1.1.Overview of the electrical network

Power systems are regarded as highly critical infrastructures for our modern societies and economies. These systems were traditionally built as vertical organizations, in which energy transfers follow a “top-to-bottom” pattern: generation, transmission, distribution and customer.

Indeed, traditional power systems have been centrally operated. Thus, most electricity generation is produced by large power plants, such as nuclear-based generators. This generation often takes place on adequate geographical sites (with sources of cooling water, fulfilling technical requirements, etc.). The energy produced is then transferred to large consumption centers, through a network of overhead-lines and underground cables, often over long distances and with relatively high voltage levels. This system was built on the basis of economy, system security and quality of supply requirements. The structure is thus very centralized and continuously monitored/controlled by hierarchical dispatching centers. In order to keep the generation-consumption balance constant, generation is instantaneously adjusted to consumption evolution by monitoring the frequency of the system. To this end, very sophisticated load forecasting models are used for anticipation purposes. Voltage is also controlled to be kept within a specified range, with various devices often being coordinated: generators, on-load tap-changing transformers, static VAR compensators, operator’s actions, etc.

However, this operating process is challenged by many factors, including:

– saturation of the current power grid and more and more operated near security limits;

– geographical and environmental constraints (increasingly difficult construction of new lines and large power plants);

– constant growth of consumption, despite the beginning of stagnation in some countries;

– system stability and security requirements (more and more expensive preventing equipment and systems);

– competitive environment of the energy market (deregulation);

– emergence of environmentally friendly small-size generation units driven by current regulations. This is particularly true within the framework of the economical incentives for renewable energies. Some of these forms of energy production can be combined with heat production (cogeneration) or even cold production (trigeneration), thus allowing higher efficiency.

These factors have contributed to the major changes that the power systems underwent by the end of 20th Century in their organization, planning and operations. The rapid development of new information and communication technologies during the same period has also opened up new perspectives for this sector.

Given this context, many countries over recent years have encouraged the development of distributed generation (DG). This generation of units concerns a different form of energy generation with a capacity ranging from several kWs to several tens of MWs (depending on the regulation of each country), and can also be coupled with heat production. It is mainly based on renewable energies such as wind turbines, photovoltaic panels (PV), biomass or geothermal and is intended to be produced locally (to be as close as possible to the end user) and transmitted over short distances. DG is currently planned to be mostly interconnected on distribution systems (low voltage (LV) or medium voltage (MV) networks). Its current development is heavily related to regulation incentives to fulfill government objectives and targets in terms of renewable energy development.

DG introduced radical changes in the industry of generation, management and distribution of electric energy. Moreover, it partly challenges the planning, design and operations of the power system. Specifically, introducing such energy sources in distribution networks on a large scale may cause several interconnection problems. Indeed, these networks were designed to be “delivery grids” and thus have limited capabilities in integrating DGs. As such, if DGs inject a significant amount of energy, there will be important consequences on energy flows within the grid namely on reversing the flows from DGs to substations whereas these networks were not designed to handle such a situation with bi-directional flows. Therefore the philosophy of management and the protection of the grid will be impacted.