Modeling and Control of Power Electronic Converters for Microgrid Applications

Preface
Contents
About the Author
Chapter 1: Introduction to the Modeling and Control of Power Electronic Converters for Microgrid Applications
	1.1 Overview
	1.2 Scope of the Book
	References
Chapter 2: Modeling and Stability Analysis of LCL-Filter-Based Voltage Source Inverters
	2.1 Introduction
	2.2 System Description
		2.2.1 Parameter Design Procedures
		2.2.2 Magnetic Integration Techniques
	2.3 Damping Methods for Internal Stability
		2.3.1 Passive Damping Methods
		2.3.2 Filter-Based Damping Methods
		2.3.3 State-Feedback-Based Damping Methods
		2.3.4 Effect of Control Delay and Application Issues
	2.4 Impedance-Based Method for External Stability
		2.4.1 Impedance-Based Stability Criterion
		2.4.2 Impedance Modeling Methods
		2.4.3 Online Impedance Measurement Techniques
		2.4.4 Stability Analysis of Multi-paralleled Grid-Connected Inverters
	2.5 Benchmark Systems for Stability Analysis
		2.5.1 Stability Evaluation Grid-Connected Inverter Using PR Controller Without Delay
		2.5.2 Stability Evaluation Grid-Connected Inverter Using PR Controller with Control Delay (Fig. 2.26)
		2.5.3 Stability Evaluation Grid-Connected Inverter Using SRF-PI Controller with Control Delay
	2.6 Conclusions
	References
Chapter 3: Controller Synthesis and Parameter Selection for Standalone Single-Phase PWM Inverters
	3.1 Introduction
	3.2 Control Structure of the Single-Phase Inverters
		3.2.1 Control Structure of the Single-Phase Inverter with the HRF-Based Control Strategy
		3.2.2 Analysis of the SRF-PI Controller
		3.2.3 Mathematic Model of the HRF-Based Control Strategy
	3.3 Step-by-Step Parameter Design
	3.4 Stability Analysis Using EMTP-ATP Simulation
	3.5 Experimental Evaluation
	3.6 Conclusion
	References
Chapter 4: Nonlinear Stability Analysis of Digital Controlled Single-Phase Standalone Inverter
	4.1 Introduction
	4.2 Mathematical Modeling with SRF Voltage Control
		4.2.1 System Modeling Under Resistive Load Condition
		4.2.2 System Modeling under Inductive-Resistive Load Condition
		4.2.3 System Modeling Under Diode Rectifier Load Condition
		4.2.4 System Modeling of the PWM Inverter in the Grid-Connected Mode
	4.3 Stability Analysis Under Parameter Variations in Voltage Loop
		4.3.1 Stability Analysis Under Resistive Load by Using Jacobian Matrix Method
		4.3.2 Stability Analysis Under Resistive Load Condition by Using Lyapunov Exponent Method
		4.3.3 Stability Analysis Under Inductive-Resistive Load Condition
		4.3.4 Stability Analysis Under Nonlinear Load Condition
	4.4 Stability Analysis Under Parameter Variations in Current Loop
		4.4.1 Stability Analysis Under Resistive Load Condition by Using Jacobian Matrix Method
		4.4.2 Stability Analysis Under Resistive Load Condition by Using Lyapunov Exponent Method
		4.4.3 Stability Analysis Under Inductive-Resistive Load Condition
		4.4.4 Stability Analysis Under Nonlinear Load Condition
	4.5 Simulation Results and Discussions
		4.5.1 Stability Evaluation with a Control Delay of 50 Microsecond
		4.5.2 Stability Evaluation with a Control Delay of 75 Microseconds
		4.5.3 Stability Evaluation with a Control Delay of 100 Microseconds
		4.5.4 Stability Evaluation with the Variation of Load Parameters
	4.6 Experimental Results
		4.6.1 Experimental Results Under Resistive Load Condition
		4.6.2 Experimental Results Under Inductive-Resistive Load Condition
		4.6.3 Experimental Results Under Nonlinear Load Condition
	4.7 Conclusion
	Appendix A: Expressions of α, β, K1, K2, K3, K4 in Eq. (4.5)
	Appendix B: Definitions of Coefficients in Eq. (4.8)
	Appendix C: Expressions of Matrix Elements in Eq. (4.13)
	References
Chapter 5: Small-Signal Modeling and Controller Synthesis of BPF-Based Droop Control for Single-Phase Islanded Microgrid
	5.1 Introduction
	5.2 Small-Signal Modeling of Single-Phase Islanded Microgrid
		5.2.1 Active and Reactive Power Controller
		5.2.2 BPF-Based Enhanced Droop Controller
		5.2.3 Complete Small-Signal Model of Single-Phase Islanded Microgrid
	5.3 Stability and Dynamic Performance Analysis
		5.3.1 Effect of Active Power Droop Coefficient
		5.3.2 Effect of Reactive Power Droop Coefficient
		5.3.3 Effect of BPF Parameters
		5.3.4 Effect of Load Transient Response
	5.4 Simulation Results from PLECS
	5.5 Simulation Results from EMTP
		5.5.1 Performance of Conventional Droop Control Scheme
		5.5.2 Performance of BPF-Based Droop Control Scheme
	5.6 Experimental Results and Discussions
	5.7 Conclusions
	Appendix
	References
Chapter 6: Enhanced Droop Control Strategy for Three-Phase Islanded Microgrid Without LBC Lines
	6.1 Introduction
	6.2 Secondary and Washout Filter-Based Control Strategies
		6.2.1 The Secondary Control for Islanded AC Microgrid
		6.2.2 Washout Filter-Based Power Sharing Strategies for Islanded AC Microgrid
		6.2.3 Equivalence Between Secondary and Washout Filter-Based Controllers
	6.3 Small-Signal Model of Generalized Washout Filter-Based Control Method
		6.3.1 Power Control Loops
		6.3.2 Equations of Voltage, Current Loop Controllers, and LCL Filters
		6.3.3 Equations of Distributed Lines and Loads
		6.3.4 Reference Frame Transformation
		6.3.5 Linearized Model of Complete DG System
		6.3.6 Small-Signal Analysis
	6.4 Simulation Results Using EMTP
		6.4.1 Conventional Droop Control Scheme
		6.4.2 Washout Filter-Based Improved Droop Control Scheme
	6.5 Hardware-in-the-Loop Results
		6.5.1 Performance of Conventional Droop Controller
		6.5.2 Performance of the Secondary Control Considering the LBC Delays and Communication Failure
		6.5.3 Performance of the Washout Filter-Based Control Method
		6.5.4 Performance of the Generalized Washout Filter-Based Control Strategy
	6.6 Experimental Results
	6.7 Conclusions
	Appendix A
	References
Chapter 7: Consensus-Based Enhanced Droop Control Scheme for Accurate Power Sharing and Voltage Restoration in Islanded Microgrids
	7.1 Introduction
	7.2 Proposed Consensus-Based Enhanced Droop Control and Steady-State Performance Analysis
		7.2.1 Graph Theory
		7.2.2 Proposed Consensus-Based Enhanced Droop Control Scheme for Power Sharing
		7.2.3 Steady-State Performance Analysis of the Proposed Consensus Control
	7.3 Local Exponential Stability Analysis in Consensus Controller
	7.4 Results and Performance Evaluations
		7.4.1 Comparison with the Conventional Droop and Secondary Control Strategies
		7.4.2 Performance Evaluations in Case of Communication Failure
	7.5 Conclusion
	References
Chapter 8: Enhanced Hierarchical Control for Islanded Microgrid Using Advanced Damping Methods
	8.1 Introduction
	8.2 Enhanced Hierarchical Control Strategy
		8.2.1 Droop Control for Microgrid
		8.2.2 Secondary Control for Microgrid
	8.3 Modeling and Controller Design of Islanded Microgrid
		8.3.1 Small-Signal Model of Power Controller
		8.3.2 Virtual Impedance Loop
		8.3.3 Inner Voltage and Current Control Loops
	8.4 Simulation Results Using EMTP
		8.4.1 Conventional Droop Control with Unequal Feeder Impedance
		8.4.2 Proposed Secondary Control Scheme with Unequal Feeder Impedance
	8.5 Experimental Results
	8.6 Conclusions
	References
Index