Protection concepts in distribution network with decentralised energy resources [Elektronische Ressource] / Biljana Hadzi-Kostova

Res Electricae Magdeburgenses
Magdeburger Forum zur Elektrotechnik




Biljana Hadzi-Kostova




Protection Concepts in Distribution Networks
with Decentralised Energy Resources












Otto-von-Guericke-Universität Magdeburg
Magdeburg 2005






Protection Concepts in Distribution Networks
with Decentralised Energy Resources








Dissertation


zur Erlangung des akademischen Grades



Doktoringenieurin
(Dr.-Ing.)




von Biljana Hadzi-Kostova
geb. am 15.08.1977 in Skopje

genehmigt durch die Fakultät Elektrotechnik und Informationstechnik
der Otto-von-Guericke-Universität Magdeburg

Gutachter: Prof. Dr.-Ing. habil. Zbigniew Styczynski
Prof. i. R. Dr. Arun G. Phadke
Dr.-Ing. Rainer Krebs
Promotionskolloquium am 25. Oktober 2005
Res Electricae Magdeburgenses
Magdeburger Forum zur Elektrotechnik, Jg. 3, Band 11, 2005

IMPRESSUM:
Herausgeber:
Prof. Dr. rer. nat. Jürgen Nitsch,
Institut für Grundlagen der Elektrotechnik und Elektromagnetische Verträglichkeit
Prof. Dr.-Ing. Zbigniew Antoni Styczynski,
Institut für Elektrische Energiesysteme
beide: Otto-von-Guericke-Universität Magdeburg, Postfach 4120, 39016
Magdeburg

V. i. S. d. P.:
Biljana Hadzi-Kostova
Otto-von-Guericke-Universität Magdeburg, Postfach 4120, 39016 Magdeburg


1. Auflage, Magdeburg, Otto-von-Guericke-Universität, 2005
Zugl.: Magdeburg, Univ., Diss., 2005
Auflage: 200
Redaktionsschluss: 2005
ISSN 1612-2526
ISBN 3-929757-84-2
© Copyright 2005 Biljana Hadzi-Kostova
Bezug über die Herausgeber
Druck: Otto-von-Guericke-Universität Magdeburg,
Abteilung Allgemeine Angelegenheiten, Postfach 4120, 39016 Magdeburg
iiPreface

This dissertation contains my research work done as an assistant at the
Institute for Electrical Power Systems at the Otto–von–Guericke-University
Magdeburg, Germany.
I would like to express my gratitude to my supervisor Prof. Dr. Z.
Styczynski for giving me the chance to work at his chair on this very
interesting engineering area.
I would like to thank Prof. i. R. Dr. A. Phadke, Virginia Technical University,
USA for being the external examiner of my dissertation and for his interest
in my work. I would also like to thank Dr.-Ing. R. Krebs, Power
Technologies Siemens, Erlangen, Germany for the very close cooperation
and the exchange of ideas as well as for being one of my examiners.
I thank my colleagues from the University of Magdeburg and the University
of Wroclaw, Poland, as well as from Siemens AG, for their co-work and
friendship.
Finally, I thank my family and friends for their support and encouragement
during the writing of this work.

Biljana Hadzi-Kostova
iiiContents
1. Introduction. Goal, thesis and work structure................................1
1.1 Introduction..........................................................................1
1.2 Goals, thesis and work structure...............................................2

2. Einleitung. Ziele, These und Struktur der Arbeit.............................5
2.1 Einleitung..............................................................................5
2.2 Ziele, These und Struktur der Arbeit .........................................6

3. Digital protection in distribution networks.....................................9
3.1 General information about protection systems ............................9
3.2 General information about numerical protection........................ 10
3.3 Functional principle of over-current protection.......................... 12
3.4 of distance protection................................ 14
3.5 of differential protection 16

4. The implementation of DER in the network and its influence on digital
protection .............................................................................. 18
4.1 Introduction. General information of the technologies of DER...... 18
4.2 Connection of DER to the network .......................................... 19
4.3 Modelling of DER for protection coordination tasks .................... 33
4.3.1 Fuel cells modelling......................................................... 33
4.3.2 Photovoltaic modelling..................................................... 34
4.3.3 Electrical energy storage devices modelling ........................ 35
4.3.4 Wind power plants modelling............................................ 36

5. The influence of a high amount of harmonics on different types of
protection devices ................................................................... 39
5.1 Introduction........................................................................ 39
5.2 Modelling distance protection in MATLAB.................................. 41
5.2.1 General information about the investigation ............................. 41
5.2.2 Steady-state algorithms................................................... 43
5.2.3 Algorithms based on DEFO ............................................... 45
5.2.4 Algorithms based on DESO 48
5.2.5 Algorithms using filter approach........................................ 49
5.2.6 Algorithms using parametric estimation ............................. 53
5.2.7 Algorithms using HANN.................................................... 55
5.3 Practical analyses of digital protection devices .......................... 61
5.4 Modelling of differential protection devices............................... 63

6. Protection systems in networks with DER.................................... 65
6.1 Introduction. Impacts of power supply systems and challenges of
protection systems ............................................................... 65
6.2 Investigations in test networks............................................... 68
6.2.1 Test networks................................................................. 68
6.2.2 Network scenarios and discussion...................................... 70
6.2.3 Analysis of the simulation results 80
iv 6.3 Implementation of the possibility of recognising the fault current
direction ............................................................................. 86
6.4 New approaches in protection systems with DER....................... 88
6.4.1 Introduction................................................................... 88
6.4.2 The standards IEC 61850 and IEC 61970 ........................... 91
6.4.3 Communication in distribution networks with DER ............. 103
6.5 New concept of network protection based on additional signal
injection............................................................................ 110

7. E-learning – The new teaching method..................................... 114
7.1 Introduction...................................................................... 114
7.2 E-learning system - Virtual protection technique ..................... 115
7.2.1 Structure of the e-learning system .................................. 115
7.2.2 Chapter contents and Realisation .................................... 115
7.3 Results of implementation of e-learning system ...................... 121

8. Conclusion........................................................................... 123

9. Zusammenfassung................................................................ 125

10. Literature............................................................................. 127

v List of Acronyms

DER decentralised energy resources
IED intelligent electronic devices
I/O input-output
HMI human-machine interface
RAM random access memory
ROM read only memory
PROM programmable ROM
CT current transformer
A/D analogue/digital
DFT discrete Fourier transformation
VT voltage transformer
LV low voltage
MV meduim
LOM loss of mains
LOS loss of grid
PCC point of common coupling
FC fuel cell
CHP combined heat and power
PEM polymer electrolyte membrane
PV photovoltaic
ESD energy storage device
DFIG double feed induction generator
DEFO differential equation of first order
DESO differential equation of second order
FFT fast Fourier transformation
HANN harmonic activated neuronal networks
LSQ least square
BP back propagation
RTDS real time digital simulator
PD protection device
RTU remote terminal unit
IT information technology
LN logical nodes
SAS substation automation system
EMS energy management system
SCADA supervisory control and data acquisition
IF interface
PMU phasor measurement unit
EES electrical energy system


vi 1. Introduction. Goal, thesis and work structure

1.1 Introduction

The digital protection technique of today joins knowledge not only from its
own field, but also from the fields of digital signal processing, power
qualit