Risk Based Assessment of Subsynchronous Resonance in AC/DC Systems (eBook)

Atia Adrees (Autor)

eBook Download: PDF

2016 | 1st ed. 2017
XX, 218 Seiten
Springer International Publishing (Verlag)
978-3-319-44947-0 (ISBN)

Infos

This relevant and timely thesis presents the pioneering use of risk-based assessment tools to analyse the interaction between electrical and mechanical systems in mixed AC/DC power networks at subsynchronous frequencies. It also discusses assessing the effect of uncertainties in the mechanical parameters of a turbine generator on SSR in a meshed network with both symmetrical and asymmetrical compensation systems.

 

The research presented has resulted in 12 publications including three top international journal papers (IEEE Transactions on Power Systems) and nine international conference publications, including two award-winning papers.

 

Inhalt

Supervisor’s Foreword 7
Parts of this thesis have been published in the following journal articles and conference proceedings:J. V. Milanovic and A. Adrees, “Identifying Generators at Risk of SSR in Meshed Compensated AC/DC Power Networks,” IEEE Transactions on Power Systems, vol. 28, pp. 4438–4447, 2013.A. Adrees and J. V. Milanovic, “Methodology for Evaluation of Risk of Subsynchronous Resonance in Meshed Compensated Networks,” IEEE Transactions on Power Systems, vol. 29, pp. 815–823, 2013.A. Adrees and J. V. Milanovic, “Optimal Compensation of Transmission Lines Based on Minimisation of the Risk of Subsynchronous Resonance,” IEEE Transactions on Power Systems, vol. 31, pp. 1038–1047, 2015.A. Adrees and J. V. Milanovic, “Subsynchronous resonance in meshed networks with HVDC lines,” IEEE Innovative Smart Grid Technologies Europe (ISGT) 2011, Manchester, U.K, 5–7 Dec. 2011.A. Adrees and J. V. Milanovic, “Effects of uncertainties in shaft mechanical parameters on maximum torsional torques in meshed networks with HVDC lines,” IEEE Transmission and Distribution Conference and Exposition (T& D) 2012, Orlando, U.S.A, 7–10 May 2012.A. Adrees and J. V. Milanovic, “The Effects of Uncertainties in Mechanical Parameters on SSR in Meshed Power Networks with Different HVDC Technologies,” IEEE International Conference on Probabilistic Methods Applied to Power Systems 2012, Istanbul, Turkey, 7–10 May 2012. Best Student Paper AwardA. Adrees and J. V. Milanovic, “Index for ranking generators based on risk of subsynchronous resonance in the network,” IEEE PowerTech (POWERTECH) 2013, Grenoble, France, 16–20 June 2013.A. Adrees and J. V. Milanovic, “Study of subsynchronous resonance in meshed compensated AC/DC network,” 2013 IREP Symposium Bulk Power System Dynamics and Control - IX Optimization, Security and Control of the Emerging Power Grid (IREP) 2013, Crete, Greece, 25–30 Aug. 2013.R. Preece, A. Adrees, and J. V. Milanovic, “Risk-based framework for assessment of operational constraints for power systems focusing on small-disturbance stability and sub-synchronous resonance,” IEEE Innovative Smart Grid Technologies Europe (ISGT) 2013, Copenhagen, Denmark, 6–9 Oct. 2013.R. Preece, A. Adrees, and J. V. Milanovic, “Risk-based framework for Establishing And Visualising Operational Constraints of power systems,” Power Systems Computation Conference (PSCC) 2014, Wroclaw, Poland, 18–22 Aug. 2014.A. Adrees, and J. V. Milanovic, “Effectiveness of Asymmetrical Series Compensation for Mitigation of SSR in Meshed Power Networks,” IEEE Innovative Smart Grid Technologies Europe (ISGT) 2014, Istanbul, Turkey, 12–15 Oct. 2014.A. Adrees, and J. V. Milanovic, “Establishing the Sensitivity of Dynamic Instability due to SSR,” IEEE PowerTech (POWERTECH) 2015, Eindhoven, Netherlands, June 29–July 2 2015.
Acknowledgements 12
Contents 13
Symbols 17
Special Symbols 18
Subscripts 18
1 Introduction 19
Abstract 19
1.1 Power System Stability 19
1.1.1 Oscillations in Power System 20
1.2 Subsynchronous Resonance 21
1.2.1 Self Excitation 21
1.2.2 Transient Torques Amplification 22
1.3 Known Cases of Subsynchronous Resonance 22
1.3.1 The Mohave Incidents 23
1.3.2 Navajo Project 24
1.3.3 HVDC Turbine Generator Interactions at Square Butte 24
1.4 HVDC Transmission 25
1.5 HVDC Technology 25
1.5.1 LCC-HVDC 25
1.5.1.1 General Operation Principle 26
1.5.1.2 Control of HVDC Systems 26
1.5.1.3 Inherent Damping Characteristics of LCC-HVDC 27
1.5.2 VSC-HVDC 28
1.5.2.1 General Topology and Operation 28
1.5.2.2 Inherent Damping Characteristics of VSC-HVDC 30
1.6 Past Research on Subsynchronous Resonance (SSR) 31
1.6.1 Analysis Methods 32
1.6.2 Potential Sources of Subsynchronous Oscillations 33
1.6.2.1 Series Capacitor Compensation of Networks 33
1.6.2.2 Device Dependent Subsynchronous Oscillations 34
1.6.3 Mitigation of SSR 36
1.6.3.1 Unit Tripping Mitigation Techniques 36
1.6.3.2 Non-unit Tripping SSR Mitigation Techniques 38
1.6.3.3 Mitigation Techniques for Torsional Interactions Due to HVDC Controllers 42
1.6.3.4 Mitigation Techniques for SSR Due to Shunt Compensators 43
1.6.3.5 Turbine Generator Model 44
1.6.3.6 Shaft Fatigue 45
1.6.3.7 VSC-HVDC 46
1.6.3.8 Uncertainty in Mechanical Parameters 46
1.6.4 Summary of Past Research 47
1.7 Research Aims and Objectives 48
1.8 Main Contributions of This Research 49
1.9 Thesis Overview 50
References 51
2 Power System Modelling and SSR Analysis Methods 57
Abstract 57
2.1 Synchronous Generators 57
2.2 Modelling Power System Components 60
2.2.1 Modelling Synchronous Generators 60
2.2.2 Modelling Turbine Generator Mechanical System 61
2.2.3 Generator Excitation Systems 64
2.2.3.1 Manual Excitation 65
2.2.3.2 Static Excitation (IEEE Type STIA) 65
2.2.3.3 DC Excitation (IEEE Type DC1A) 66
2.2.4 Power System Stabilizers 66
2.2.5 Transmission Lines 67
2.2.6 Loads 67
2.3 HVDC System Modelling 68
2.3.1 LCC-HVDC Converters 68
2.3.2 Converter Transformer Model 69
2.3.3 LCC Converter Controls 69
2.3.4 VSC-HVDC Converters 69
2.3.5 VSC-HVDC Controls 70
2.3.5.1 Outer Control Loops 71
DC Voltage Control 71
AC Voltage Control 72
Active and Reactive Power Control 72
2.3.6 VSC Control Structure 73
2.4 Thyristor Controlled Series Capacitors (TCSCs) 74
2.5 SSR Analysis Methods 76
2.5.1 Frequency Scanning Method 76
2.5.2 Eigenvalue Analysis 78
2.5.3 Electromagnetic Transients Simulations 80
2.6 Comparison of SSR Analysis Methods 80
2.7 Test Networks 81
2.7.1 Test Network 1 81
2.7.2 Test Network 2 82
2.8 Summary 82
References 83
3 Ranking of Generators Based on the Exposure to Subsynchronous Resonance 85
Abstract 85
3.1 Frequency Scanning Methods 85
3.1.1 Simplified Analytical Method 85
3.1.1.1 Self Excitation Due to Induction Generator Effect 86
3.1.1.2 Self Excitation Due to Electrical and Mechanical System Interaction 87
3.1.1.3 Transient Torques Amplification Due to SSR 87
3.2 Two Axis Analytical Method 88
3.3 Test Signal Method 89
3.4 Choice of Frequency Scanning Method 90
3.4.1 Validation of Frequency Scanning Program 91
3.5 Modified Test System 1 92
3.6 Indices for Assessing Generator Exposure to SSR 93
3.7 Index for Assessing Self Excitation Due to Torsional Interactions (RISSR) 95
3.7.1 RISSR for 70 % Compensation 98
3.7.2 Effect of Compensation Level and Network Topology on Ranking of Generators Using RISSR 100
3.7.2.1 Effect of Compensation Level 100
3.7.2.2 Stability Analysis of Torsional Modes 102
3.7.2.3 Generator Radially Connected to Compensated Line 105
3.8 Index for Assessing Amplification of Transients Torques 108
3.9 Ranking of the Generators 112
3.10 Verification of Generator Ranking 112
3.11 Effect of Different Compensation of Lines 114
3.11.1 Uncompensated Line in Parallel with Compensated Line 114
3.11.2 Uneven Compensation of Parallel Lines 115
3.11.3 Asymmetrical Compensation 117
3.11.3.1 Series Resonance Scheme 117
3.11.3.2 Parallel Resonance Scheme 118
3.11.3.3 Applicability of Developed SSR Index in Systems with Asymmetrical Lines 118
3.12 Effect of VSC-HVDC Line on Generator Ranking 120
3.13 Summary 122
References 123
4 Methodology for the Evaluation of Risk of Subsynchronous Resonance 125
Abstract 125
4.1 Methodology for Risk Evaluation of SSR 126
4.1.1 Line Outage Model 126
4.1.2 Selecting System Contingencies and Calculating Their Probabilities 127
4.1.2.1 Evaluating the Severity of SSR for Selected System Contingencies 127
4.1.3 Calculation of Risk Index 129
4.1.3.1 Assessing the Degree of Risk (Qualitative Approach) 129
4.1.4 Modified Test System 130
4.2 Risk Evaluation of SSR 131
4.2.1 Example of Risk Evaluation for G1 131
4.2.2 Risk Matrix 137
4.3 Summary 142
References 143
5 Influence of Uncertainties in Mechanical Parameters 144
Abstract 144
5.1 Influence of Uncertainties in Meshed AC/DC Networks 144
5.1.1 Modification in the Test System 145
5.1.2 Modelling Uncertainty in Mechanical Parameters 147
5.1.3 Analysis Methods 147
5.1.4 The Influence of Uncertainties 147
5.1.4.1 Influence of Uncertainties for Different Operating Conditions of a Turbine Generator 151
5.1.5 Results of Modal Analysis 157
5.2 LCC-HVDC Versus VSC-HVDC 159
5.3 Effect of Uncertainty in Mechanical Parameters on Peak Torques Due to Different Types of Faults 160
5.3.1 Three Phase Short Circuit 160
5.3.1.1 P = 585 MW 160
5.3.1.2 P = 700 MW 162
5.3.1.3 P = 840 164
5.3.2 Two Phase to Ground Short Circuit 166
5.3.2.1 Two Phase Short Circuit 168
5.3.2.2 Single Line to Ground Fault 171
5.3.3 Influence of Different Types of Lines 174
5.4 Effect of Uncertainty in Mechanical Parameters on Risk of Subsynchronous Resonance with Different Types of Compensation Schemes 176
5.4.1 Modelling Uncertainty in Mechanical Parameters of Turbine Generator 176
5.5 Effect of Uncertainty on Dynamic Instability 177
5.5.1 Critically Compensated System 177
5.5.2 SSR Analysis 177
5.6 Effect of Uncertainty on Transient Torque Amplification 178
5.7 Dynamic Stability Analysis in the Presence of Uncertainties in Shaft Mechanical Parameters 179
5.7.1 Dynamic Stability Analysis in the Presence of Uncertainties in Shaft Mechanical Parameters 181
5.7.2 Effect of Uncertainties on Level of Risk of SSR for Different Compensation Schemes 185
5.8 Summary 186
References 187
6 Optimal Series Compensation of Lines to Minimize the Exposure of Generators to SSR 188
Abstract 188
6.1 Mitigating SSR with TCSC 188
6.2 Methodology 189
6.2.1 SSR Severity Measure 190
6.2.2 Selection of Network Contingencies 190
6.2.3 Probability of Network Contingencies 190
6.2.4 Assessment of Risk of SSR 190
6.2.5 Modified Test System 191
6.2.6 Application of Proposed Method 193
6.2.7 Validation of Results with EMT Simulation 199
6.3 Summary 201
References 201
7 Future Work and Conclusions 203
Abstract 203
7.1 Conclusions 203
7.2 Future Work 205
References 207
Appendix A: Network Data 215
A.1 NETS-NYPS Test Network Data 215
Outline placeholder 1
A.1.1 Line Impedances 215
A.1.2 Load Flow Data 218
A.1.2.1 Generator Dynamic Data 219
A.2 Two Area Test Network Data 221
Outline placeholder 1
A.2.1 Line Impedance Data 221
A.2.2 Load Flow Data 221
A.2.3 Generator Dynamic Data 222
A.3 HVDC System Details 222
Outline placeholder 1
A.3.1 VSC System Details 222
A.3.2 LCC-HVDC Control Setting 223
References 223
Appendix B: Risk Indices Data 224
B.1 Generators Data 224
B.2 Negative Damping Calculated for 50 % 225
B.3 Negative Damping with 30 % Compensation Level 226
B.4 Generators in Radial Connection with 70 % Compensation 227
B.5 Generators in Radial Connection with 50 % Compensation 228
B.6 Generators in Radial Connection with 30 % Compensation 229
B.7 70 % Per Phase Compensation in Normal Network Configuration 229
Outline placeholder 1
B.7.1 70 % Per Phase Compensation in Normal Network Configuration 230
B.7.1.1 Uncompensated Line in Parallel with Compensated Line 230
B.8 Uneven Compensation of Lines 232
References 233

Produkt-Details

• Erscheint lt. Verlag: 4.10.2016
• Reihe/Serie: Springer Theses
• Reihe/Serie: Springer Theses
• Zusatzinfo: XX, 218 p. 120 illus., 92 illus. in color.
• Verlagsort: Cham
• Sprache: englisch
• Themenwelt: Mathematik / Informatik ► Mathematik ► Statistik
• Themenwelt: Naturwissenschaften ► Physik / Astronomie
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: Generator Assessment • Power Systems • Probabilistic Approach • Quality Control, Reliability, Safety and Risk • risk analysis • SSR
• ISBN-10: 3-319-44947-8 / 3319449478
• ISBN-13: 978-3-319-44947-0 / 9783319449470