Comprehensive resource discussing specific challenges and control solutions associated with operating inverter-based resources in weak grid scenarios
Weak Grid Integration of Inverter-Based Resources delves into current operational challenges and control solutions associated with inverter-based resources (IBR) in weak grid scenarios, with real-world examples included throughout to elucidate key concepts. The book introduces the control architecture of IBR power plants and the underlying AC circuit topology, providing readers with a comprehensive overview of the system. It discusses specific operational challenges and examines how they relate to the grid-following control system and circuit characteristics. The book also reviews various grid-forming control designs and their role in enhancing weak-grid operation, while analyzing potential challenges arising from interactions between IBRs and series or shunt compensation. In addition, it investigates the different fault behaviors associated with grid-following and grid-forming control.
Written by two highly qualified experts, Weak Grid Integration of Inverter-Based Resources includes information on:
- IBR inverter-level and power plant-level control logic
- Root causes of a variety of oscillation phenomena
- Impact of series and shunt compensation on grid characteristics
- Stability analysis and associated modeling techniques, including complex vector-based modeling and analysis and forming customized feedback systems
- Fault behaviors and their connection to IBR control logic
Comprehensive in scope, Weak Grid Integration of Inverter-Based Resources appeals to a wide spectrum of readers in the field, including professionals in the power industry and university students in related programs of study.
Table of Contents:
Preface xi
IEEE Press Offshore Wind Energy Collection xv
About the Series Editor xvi
About the Authors xvii
1 Inverter-based Resource Power Plant Control and AC Delivery 1
1.1 Inverter-based Resource Grid Integration Circuit Topology 1
1.2 Inverter-level Control Logic 2
1.2.1 Inner Current Control 4
1.2.2 Synchronizing Units: Grid-following Versus Grid-forming 7
1.2.3 Outer Control Functions 10
1.3 Power Plant-level Control Logic 13
1.4 Study Methods: Analysis and Electromagnetic Transient Simulation 15
1.5 Summary 15
References 15
2 Operational Challenges and Root Cause Analysis 17
2.1 PLL Loss of Synchronism 17
2.1.1 Analysis of Phase Angle Jump 21
2.1.2 EMT Simulation Results 23
2.1.3 Mitigation Strategy 25
2.2 Voltage Oscillations Below 10 Hz 26
2.2.1 Voltage–Reactive Power Feedback System 27
2.2.2 The Role of Real Power 31
2.2.3 Inclusion of PLL Dynamics 40
2.2.4 Interactions of DC-link Voltage Control, PLL, and AC Voltage Control 42
2.3 Oscillations Above 10 Hz 51
2.3.1 Complex Grid Impedance 56
2.3.2 Analysis 58
2.4 Oscillatory Versus Monotonic Dynamics: Another Perspective 63
2.4.1 The Simplified System Model 64
2.4.2 Open-loop Analysis Via MIMO System Decomposition 67
2.4.3 EMT Testbed and Simulation Results 75
2.4.4 Concluding Remarks 80
2.5 Countermeasures 81
2.5.1 Plant-level Control 81
2.5.2 Inverter-level Voltage Stability Enhancement 82
References 88
3 Grid-forming Control 91
3.1 Why Grid-forming Control? 91
3.1.1 Grid Codes 91
3.1.2 Benefits of GFM 92
3.2 Multi-loop GFM Control: Virtual Admittance 95
3.2.1 Strong Grid Fault Ride-through Tests 98
3.2.2 Weak Grid Fault Ride-through Tests 100
3.3 Multi-loop GFM Control: Vector Control 101
3.3.1 Strong Grid Fault Ride-through Tests 103
3.3.2 Weak Grid Fault Ride-through Tests 105
3.4 Single-loop Control 107
3.4.1 Strong Grid Fault Ride-through Tests 109
3.4.2 Weak Grid Fault Ride-through Tests 109
3.5 Summary 110
References 114
4 Interactions of Inverter-based Resources with Series or Shunt Compensation 115
4.1 Introduction 115
4.2 Sources and Grid Characteristics 116
4.2.1 Series-compensated Circuits Powered by Different Sources 116
4.2.2 Shunt-compensated Circuits Powered by Different Sources 119
4.3 Interactions of GFL-IBR and Series or Shunt Compensation 122
4.3.1 Influence of Series or Shunt Compensation on Grid Impedance 122
4.3.2 Feedback Systems and Stability Analysis 126
4.3.3 Remarks 128
4.4 Interactions of GFM-IBR and Series Compensation 130
4.4.1 EMT Studies 130
4.4.2 Analysis 132
4.4.3 Remarks 136
References 136
5 Fault Behavior of Inverter-based Resource-penetrated Power Grids 139
5.1 Sequence Network Interconnections 140
5.2 IBR’s Representation in Circuits 140
5.3 Single-phase Open-circuit Faults 142
5.3.1 EMT Testbeds and Simulation Results 143
5.3.2 Analysis 144
5.3.3 Remarks 148
5.4 Unbalanced Ground Faults 148
5.4.1 Interconnected Sequence Network 151
5.4.2 EMT Simulation Results 153
5.4.3 Fault Behavior of a GFM-IBR System 153
5.4.4 Remarks 155
References 155
Index 157
About the Author :
Zhixin Miao, PhD, is a Professor in the Department of Electrical Engineering, University of South Florida, Tampa FL. Prior to becoming a researcher, he worked in a variety of engineering roles.
Lingling Fan, PhD, is a Professor in the Department of Electrical Engineering, University of South Florida, Tampa FL. She is an IEEE Fellow and the recipient of IEEE Power and Energy Society’s 2025 Wanda Reder Pioneer in Power Award.
