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Flexible Distribution Systems Through the Application of Multi Back-To-Back Converters : Concept, Implementation and Experimental Verification

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Flexible Distribution Systems Through the Application of Multi Back-To-Back Converters : Concept, Implementation and Experimental Verification Flexible distribution systems through the application of multi back-to-back converters : concept, implementation and experimental verification Citation for published version (APA): Graaff, de, R. A. A. (2010). Flexible distribution systems through the application of multi back-to-back converters : concept, implementation and experimental verification. Technische Universiteit Eindhoven. https://doi.org/10.6100/IR673052 DOI: 10.6100/IR673052 Document status and date: Published: 01/01/2010 Document Version: Publisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication: • A submitted manuscript is the version of the article upon submission and before peer-review. 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If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license above, please follow below link for the End User Agreement: www.tue.nl/taverne Take down policy If you believe that this document breaches copyright please contact us at: [email protected] providing details and we will investigate your claim. Download date: 06. Oct. 2021 Flexible distribution systems through the application of multi back-to-back converters: Concept, implementation and experimental verification PROEFSCHRIFT ter verkrijging van de graad van doctor aan de Technische Universiteit Eindhoven, op gezag van de rector magnificus, prof.dr.ir. C.J. van Duijn, voor een commissie aangewezen door het College voor promoties in het openbaar te verdedigen op woensdag 26 mei 2010 om 14.00 uur door Roald Antonius Adrianus de Graaff geboren te Waalwijk Dit proefschrift is goedgekeurd door de promotor: prof.ir. W.L. Kling Copromotor: dr. J.L. Duarte Copyright © 2010 R.A.A. de Graaff All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic, mechan- ical, including photocopy, recording, or any information storage and retrieval system, without the prior written permission of the copyright owner. The work leading to this thesis was supported by KEMA and the IOP-EMVT program of SenterNovem. CIP-DATA LIBRARY TECHNISCHE UNIVERSITEIT EIND- HOVEN Graaff, Roald A.A. de Flexible distribution systems through the application of multi back-to-back converters: Concept, implementation and experi- mental verification / by Roald Antonius Adrianus de Graaff. - Eindhoven: Technische Universiteit Eindhoven, 2010. Proefschrift. - ISBN 978-90-386-2220-0 NUR 959 Trefw.: Elektriciteitsdistributie / Vermogenselektronica / Ver- mogenssturing / Besturing elektriciteitsdistributie / Span- ningskwaliteit / Spanningsregeling Subject headings: Power distribution / Power electronics / Load flow control / Power distribution control / Power quality / Voltage control To Susana To my parents Promotor: prof.ir. W.L. Kling, TU/e Copromotor: dr. J.L. Duarte, TU/e Core committee: prof.dr.ir. R.W. De Doncker, RWTH Aachen University prof.dr. E. Lomonova, TU/e prof.dr. J.A. Pe¸cas Lopes, University of Porto Other members: prof.dr.ir. J.H. Blom (reserve), TU/e dr.ir. F. van Overbeeke, EMforce prof.dr. A.G. Tijhuis (chairman), TU/e ir. P.T.M. Vaessen, KEMA Contents List of Figures v List of Tables ix Abstract xi Samenvatting xv 1 Introduction 1 1.1 Changes in electrical power generation ........... 2 1.2 Changes in the organization of power systems ....... 4 1.3 Consequences for the distribution network ......... 5 1.4 Ongoing research ....................... 6 1.4.1 Communication and automation .......... 8 1.4.2 Load control ..................... 8 1.4.3 Generation control .................. 9 1.4.4 Storage ........................ 10 1.4.5 Power electronics ................... 10 1.4.6 Active distribution networks ............ 11 1.5 Research objective ...................... 11 1.6 Research questions ...................... 12 1.7 Research approach ...................... 12 1.8 IOP-EMVT programme ................... 13 1.9 Outline of the thesis ..................... 15 1.10 Publications .......................... 16 2 Distribution systems 17 2.1 The network operator’s role ................. 17 2.2 Network topology and redundancy ............. 19 2.2.1 Network topology .................. 19 2.2.2 Redundancy ...................... 20 2.3 Power quality aspects .................... 21 2.3.1 Steady state voltage amplitude ........... 21 i ii Contents 2.3.2 Flicker ......................... 23 2.3.3 Voltage dips ...................... 24 2.3.4 Phase angle jumps .................. 25 2.3.5 Power frequency ................... 26 2.4 Voltage control ........................ 26 2.5 Conclusion .......................... 27 3 FACTS in distribution systems 29 3.1 Principles of power flow control ............... 29 3.1.1 Power flow in overhead line ............. 30 3.1.2 Power flow in underground cable .......... 35 3.2 FACTS technologies ..................... 36 3.2.1 Solid-state switching devices ............ 36 3.2.2 Converter topologies and switching strategies . 37 3.2.3 Mechanical switches ................. 39 3.3 FACTS and D-FACTS applications ............. 40 3.3.1 Shunt FACTS and D-FACTS devices ........ 41 3.3.2 Series FACTS and D-FACTS devices ........ 45 3.3.3 Mixed form FACTS and D-FACTS devices . 46 3.4 Conclusion .......................... 52 4 Functional concept of the Intelligent Node 55 4.1 Facilitating increased loading ................ 56 4.1.1 Controlled sharing of redundancy .......... 56 4.1.2 Controlled power exchange between grid areas . 60 4.2 Controlling voltage profiles ................. 61 4.2.1 Example application ................. 63 4.3 Voltage dip mitigation .................... 70 4.3.1 Example application ................. 71 4.4 Possible Intelligent Node topologies ............. 74 4.4.1 Power electronics controlled auto transformers . 74 4.4.2 Power electronics controlled series impedances . 75 4.4.3 Power electronics converters ............. 76 4.5 Conclusion .......................... 77 5 Intelligent Node control and protection 79 5.1 Basic converter controls ................... 79 5.1.1 Controller discretization ............... 81 5.1.2 AC current control .................. 82 5.1.3 AC voltage control .................. 83 5.1.4 Active and reactive power control .......... 85 5.1.5 DC bus voltage control ............... 85 5.2 IN response to unplanned power system events ...... 86 5.2.1 Voltage dip mitigation by injecting reactive power 88 Contents iii 5.2.2 IN protection concept ................ 94 5.3 IN role in planned power system events .......... 96 5.3.1 Energization and de-energization .......... 96 5.3.2 Disconnecting grid areas ............... 97 5.3.3 Connecting grid areas ................103 5.4 Conclusion ..........................114 6 Laboratory-scale demonstration 115 6.1 Experimental set-up .....................115 6.1.1 Converter control implementation .........117 6.1.2 Modeling of experimental set-up ..........118 6.2 Basic converter step responses ................119 6.2.1 Changing power reference values ..........120 6.2.2 Changing voltage reference value ..........121 6.2.3 Changing load ....................121 6.3 Transition from radial to meshed operation ........124 6.3.1 Synchronization ...................124 6.3.2 Three-phase load-break switch closing .......124 6.3.3 Phase-by-phase load-break switch closing . 127 6.3.4 Ensuring load-break switch closing detection . 131 6.4 Transition from meshed to radial operation ........132 6.4.1 Three-phase load-break switch opening .......133 6.4.2 Phase-by-phase load-break switch opening . 134 6.5 Voltage dip and swell mitigation ..............136 6.6 Conclusion ..........................137 7 Conclusions, thesis contribution and recommendations 139 7.1 Conclusions ..........................139 7.2 Thesis contribution ......................143 7.3 Recommendations ......................144 References 147 Abbreviations, symbols and notations 159 A DC current of AC/DC converter 163 A.1 DC link current in single phase voltage source converter . 163 A.2 DC link current in three-phase voltage source converter . 164 B Simulations and experimental results practical set-up 167 Acknowledgements 185 Curriculum vitae 187 List of Figures 1.1 Small and medium scale renewable energy sources. ...... 3 1.2 Google Timelines results for selected search terms. ...... 7 1.3 Structure of the IOP-EMVT Intelligent Power Systems project. 14 2.1 Types of medium and low voltage grids.
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