Model Predictive Control of Wind Energy Conversion Systems E-Book

Venkata Yaramasu

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Serie: IEEE Press Series on Power Engineering
• Sprache: Englisch

Seitenzahl: 918

Veröffentlichungsjahr: 2016

Beschreibung

Model Predictive Control of Wind Energy Conversion Systems addresses the predicative control strategy that has emerged as a promising digital control tool within the field of power electronics, variable-speed motor drives, and energy conversion systems.

The authors provide a comprehensive analysis on the model predictive control of power converters employed in a wide variety of variable-speed wind energy conversion systems (WECS). The contents of this book includes an overview of wind energy system configurations, power converters for variable-speed WECS, digital control techniques, MPC, modeling of power converters and wind generators for MPC design. Other topics include the mapping of continuous-time models to discrete-time models by various exact, approximate, and quasi-exact discretization methods, modeling and control of wind turbine grid-side two-level and multilevel voltage source converters. The authors also focus on the MPC of several power converter configurations for full variable-speed permanent magnet synchronous generator based WECS, squirrel-cage induction generator based WECS, and semi-variable-speed doubly fed induction generator based WECS. Furthermore, this book:

• Analyzes a wide variety of practical WECS, illustrating important concepts with case studies, simulations, and experimental results
• Provides a step-by-step design procedure for the development of predictive control schemes for various WECS configurations
• Describes continuous- and discrete-time modeling of wind generators and power converters, weighting factor selection, discretization methods, and extrapolation techniques
• Presents useful material for other power electronic applications such as variable-speed motor drives, power quality conditioners, electric vehicles, photovoltaic energy systems, distributed generation, and high-voltage direct current transmission.
• Explores S-Function Builder programming in MATLAB environment to implement various MPC strategies through the companion website

Reflecting the latest technologies in the field, Model Predictive Control of Wind Energy Conversion Systems is a valuable reference for academic researchers, practicing engineers, and other professionals. It can also be used as a textbook for graduate-level and advanced undergraduate courses.

Leseprobe

IEEE Press445 Hoes LanePiscataway, NJ 08854

IEEE Press Editorial BoardTariq Samad, Editor in Chief

George W. Arnold

Xiaoou Li

Ray Perez

Giancarlo Fortino

Vladimir Lumelsky

Linda Shafer

Dmitry Goldgof

Pui-In Mak

Zidong Wang

Ekram Hossain

Jeffrey Nanzer

MengChu Zhou

MODEL PREDICTIVECONTROL OF WINDENERGY CONVERSIONSYSTEMS

VENKATA YARAMASU

BIN WU

Copyright © 2017 by The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey. Published simultaneously in Canada.

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, [phone], fax [phone], or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, [phone], fax [phone], or online at http://www.wiley.com/go/permission.

Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.

For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at [phone], outside the United States at [phone] or fax [phone].

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com.

Library of Congress Cataloging-in-Publication Data is available.

ISBN: 978-1-118-98858-9

To my parents Subbayamma and Veeraiah

V.Y.

To my parents Lingen and Peifang and wife Janice

B.W.

CONTENTS

About the Authors

Preface

Acknowledgments

Acronyms

Symbols

Part I Preliminaries

Chapter 1 Basics of Wind Energy Conversion Systems (WECS)

1.1 Introduction

1.2 Wind Energy Preliminaries

1.2.1 Installed Wind Power Capacity

1.2.2 Wind Kinetic Energy to Electric Energy Conversion

1.2.3 Classification of Wind Energy Technologies

1.3 Major Components of WECS

1.3.1 Mechanical Components

1.3.2 Electrical Components

1.3.3 Mechanical and Electrical Control Systems

1.4 Grid Code Requirements for High-Power WECS

1.4.1 Fault Ride-Through

1.4.2 Reactive Power Generation

1.5 WECS Commercial Configurations

1.5.1 Type 1 WECS Configuration

1.5.2 Type 2 WECS Configuration

1.5.3 Type 3 WECS Configuration

1.5.4 Type 4 WECS Configuration

1.5.5 Type 5 WECS Configuration

1.5.6 Comparison of WECS Configurations

1.6 Power Electronics in Wind Energy Systems

1.7 Control of Wind Energy Systems

1.7.1 TSO/DSO Supervisory Control (Level VI)

1.7.2 Wind Farm Centralized Control (Level V)

1.7.3 WT Centralized Control (Level IV)

1.7.4 Grid Integration and MPPT Control (Level III)

1.7.5 Power Converter, Wind Generator, and Grid Control (Level I and II)

1.8 Finite Control-Set Model Predictive Control

1.8.1 Main Features of FCS-MPC

1.8.2 Challenges of FCS-MPC

1.9 Classical and Model Predictive Control of WECS

1.9.1 Classical Control of WECS

1.9.2 Model Predictive Control of WECS

1.9.3 Comparison of Classical and Model Predictive Control

1.10 Concluding Remarks

References

Chapter 2 Review of Generator-Converter Configurations for WECS

2.1 Introduction

2.2 Requirements for Power Converters in MW-WECS

2.3 Overview of Power Converters for WECS

2.4 Back-to-Back Connected Power Converters

2.4.1 Low-Voltage BTB Converters

2.4.2 Medium-Voltage BTB Converters

2.4.3 Comparison of BTB Power Converters

2.5 Passive Generator-side Power Converters

2.5.1 Low-Voltage PGS Converters

2.5.2 Medium-Voltage PGS Converters

2.6 Power Converters for Multiphase Generators

2.6.1 Power Converters for Six-Phase Generators

2.6.2 Power Converters for Open-Winding Generators

2.7 Power Converters without an Intermediate DC Link

2.7.1 Low-Voltage Matrix Converters

2.7.2 Medium-Voltage Matrix Converters

2.8 Concluding Remarks

References

Chapter 3 Overview of Digital Control Techniques

3.1 Introduction

3.2 The Past, Present, and Future of Control Platforms

3.3 Reference Frame Theory

3.3.1 Definition of Natural Frame Space Phasor

3.3.2 Transformation Between Natural and Stationary Frames

3.3.3 Transformation Between Natural and Synchronous Frames

3.3.4 Transformation Between Stationary and Synchronous Frames

3.4 Digital Control of Power Conversion Systems

3.4.1 Block Diagram of Digital Current Control

3.4.2 Model of Two-Level VSC for Digital Current Control

3.5 Classical Control Techniques

3.5.1 Hysteresis Control

3.5.2 Linear Control

3.6 Advanced Control Techniques

3.6.1 Sliding Mode Control

3.6.2 Intelligent Control

3.7 Predictive Control Techniques

3.7.1 Predictive Control with Modulation

3.7.2 Predictive Control without Modulation

3.8 Comparison of Digital Control Techniques

3.9 Concluding Remarks

References

Chapter 4 Fundamentals of Model Predictive Control

4.1 Introduction

4.2 Sampled-Data Model

4.3 Basics of Model Predictive Control

4.3.1 Operating Principle

4.3.2 Design Procedure

4.3.3 Implementation of Control Scheme

4.3.4 Stability-Related Issues

4.4 Cost Function Flexibility

4.4.1 Primary Control Objectives

4.4.2 Secondary Control Objectives

4.5 Weighting Factor Selection

4.5.1 Heuristic Selection

4.5.2 Per-Unit Method

4.5.3 LookupTable-Based Selection

4.5.4 Multiobjective Ranking Algorithm

4.6 Delay Compensation Methods

4.6.1 Estimation +Prediction Approach

4.6.2 Prediction +Double Prediction Approach

4.6.3 Prediction +Prediction Approach

4.6.4 Long Prediction Horizons

4.7 Extrapolation Techniques

4.7.1 Discrete Signal Generator

4.7.2 Vector Angle Extrapolation

4.7.3 Lagrange Extrapolation

4.8 Selection of Sampling Time

4.9 Concluding Remarks

References

Part II Modeling of power converters and wind generators

Chapter 5 Modeling of Power Converters for Model Predictive Control

5.1 Introduction

5.2 Objectives for the Modeling of Power Converters

5.3 Notation Employed for the Modeling

5.4 Two-Level Voltage Source Converter

5.4.1 Power Circuit

5.4.2 Operating Modes

5.4.3 Model of Output AC Voltages

5.4.4 Model of Input DC Branch Currents

5.5 Extensions to 2L-VSC Modeling

5.5.1 Modeling of Multiphase 2L-VSC

5.5.2 Modeling of BTB 2L-VSC

5.6 Neutral-Point Clamped Converter

5.6.1 Power Circuit

5.6.2 Operating Modes

5.6.3 Model of Output AC Voltages

5.6.4 Model of Input DC Branch Currents

5.7 Extensions to NPC Converter Modeling

5.7.1 Modeling of Multilevel and Multiphase DCC

5.7.2 Modeling of BTB NPC Converter

5.8 Modeling of Other Power Converters

5.8.1 Three-Level Flying Capacitor Converter

5.8.2 Current Source Converter

5.8.3 Direct Matrix Converter

5.8.4 Indirect Matrix Converter

5.9 Concluding Remarks

References

Chapter 6 Modeling of Wind Generators for Model Predictive Control

6.1 Introduction

6.2 Overview of Wind Generators for Variable-Speed WECS

6.2.1 Synchronous Generators for WECS

6.2.2 Induction Generators for WECS

6.3 Objectives for the Dynamic Modeling of Wind Generators

6.4 Notation Employed for the Dynamic Modeling

6.5 Modeling of Permanent Magnet Synchronous Generator

6.5.1 Stationary Frame Model

6.5.2 Stator Voltages in Synchronous Frame

6.5.3 Stator Flux Linkages in Synchronous Frame

6.5.4 Stator Current Dynamics in Synchronous Frame

6.5.5 Stator Active and Reactive Power

6.5.6 Electromagnetic Torque and Rotor Speed

6.6 Simulation of Permanent Magnet Synchronous Generator

6.7 Modeling of Induction Generator

6.7.1 Space Vector Model

6.7.2 Modeling in Arbitrary Reference Frame

6.7.3 Modeling in Synchronous Reference Frame

6.7.4 Modeling in Stationary Reference Frame

6.8 Simulation of Induction Generator

6.9 Generator Dynamic Models for Predictive Control

6.10 Concluding Remarks

References

Chapter 7 Mapping of Continuous-Time Models to Discrete-Time Models

7.1 Introduction

7.2 Model Predictive Control of WECS

7.3 Correlation Between CT and DT Models

7.3.1 CT and DT State-Space Equations

7.3.2 CT and DT Transfer Functions

7.4 Overview of Discretization Methods

7.5 Exact Discretization by ZOH Method

7.6 Approximate Discretization Methods

7.6.1 Forward Euler Approximation

7.6.2 Backward Euler Approximation

7.6.3 Approximation by Bilinear Transformation

7.7 Quasi-Exact Discretization Methods

7.7.1 Matrix Factorization

7.7.2 Truncated Taylor Series

7.8 Comparison of Discretization Methods

7.9 Offline Calculation of DT Parameters Using

MATLAB

7.10 Concluding Remarks

References

Part III Control of variable-speed wecs

Chapter 8 Control of Grid-side Converters in WECS

8.1 Introduction

8.2 Configuration of GSCs in Type 3 and 4 WECS

8.2.1 Single-Stage Power Conversion

8.2.2 Two-Stage Power Conversion

8.2.3 Three-Stage Power Conversion

8.3 Design and Control of GSC

8.3.1 Design of Passive Components

8.3.2 Design of Reference DC-Bus Voltage

8.3.3 Definition of Grid Power Factor

8.3.4 Grid Voltage Orientation

8.4 Modeling of Three-Phase GSC

8.4.1 Modeling of

abc

-Frame Grid Currents and Powers

8.4.2 Modeling of

αβ

-Frame Grid Currents and Powers

8.4.3 Modeling of

dq

-Frame Grid Currents and Powers

8.4.4 Modeling of VSI Output Voltages

8.4.5 Modeling of DC Link Capacitors Voltage in NPC Inverter

8.5 Calculation of Reference Grid-side Variables

8.5.1 Generator-side MPPT

8.5.2 Grid-side MPPT

8.6 Predictive Current Control of 2L-VSI in

dq

-Frame

8.6.1 Design Procedure

8.6.2 Control Algorithm

8.6.3 Comparison of the PCC Design with VOC

8.6.4 Comparison of GSC Performance with Passive Load Case

8.6.5 Switching Frequency Regulation

8.7 Predictive Current Control of NPC Inverter in

αβ

-Frame

8.7.1 Design Procedure

8.7.2 Control Algorithm

8.8 Predictive Power Control of NPC Inverter with Grid-side MPPT

8.8.1 Design Procedure

8.8.2 Control Algorithm

8.9 Real-Time Implementation of MPC Schemes

8.10 Concluding Remarks

References

Chapter 9 Control of PMSG WECS with Back-to-Back Connected Converters

9.1 Introduction

9.2 Configuration of PMSG WECS with BTB Converters

9.2.1 PMSG WECS with LV BTB Converters

9.2.2 PMSG WECS with MV BTB Converters

9.2.3 Power Flow in PMSG WECS

9.3 Modeling of Permanent Magnet Synchronous Generator

9.3.1 Steady-State Models of PMSG

9.3.2 Continuous-Time Dynamic Models of PMSG

9.3.3 Discrete-Time Dynamic Models of PMSG

9.4 Control of Permanent Magnet Synchronous Generator

9.4.1 Zero

d

-axis Current Control

9.4.2 Maximum Torque per Ampere Control

9.5 Digital Control of BTB Converter-Based PMSG WECS

9.5.1 Block Diagram of the Digital Control System

9.5.2 Control Requirements

9.5.3 Notation of Variables

9.5.4 Calculation of Reference Control Variables

9.6 Predictive Current Control of BTB 2L-VSC-Based PMSG WECS

9.6.1 Generator-side Control Scheme

9.6.2 Grid-side Control Scheme

9.6.3 Control Algorithm

9.7 Predictive Current Control of BTB-NPC-Converter-Based PMSG WECS

9.7.1 Generator-side Control Scheme

9.7.2 Grid-side Control Scheme

9.7.3 Control Algorithm

9.7.4 Extension of PCC to Other Multilevel Converters

9.8 Predictive Torque Control of BTB 2L-VSC-Based PMSG WECS

9.8.1 Generator-side Control Scheme

9.8.2 Control Algorithm

9.8.3 Extension of PTC to BTB NPC Converter

9.9 Other MPC Schemes for PMSG WECS

9.9.1 Predictive Power Control

9.9.2 Predictive Speed Control

9.10 Real-Time Implementation of MPC Schemes

9.11 Concluding Remarks

References

Chapter 10 Control of PMSG WECS with Passive Generator-side Converters

10.1 Introduction

10.2 Configuration of PMSG WECS with PGS Converters

10.2.1 PMSG WECS with LV PGS Converters

10.2.2 PMSG WECS with MV PGS Converters

10.2.3 Comparison Between BTB and PGS Converters

10.3 Modeling of the Two-Level Boost Converter

10.3.1 Power Circuit

10.3.2 Operating Modes

10.3.3 Continuous-Time Model

10.3.4 Discrete-Time Model

10.4 Modeling of the Three-Level Boost Converter

10.4.1 Power Circuit

10.4.2 Operating Modes

10.4.3 Continuous-Time Model

10.4.4 Discrete-Time Model

10.4.5 Extension of Modeling to Multilevel Boost Converters

10.5 Digital Control of PGS Converter-Based PMSG WECS

10.5.1 Block Diagram of Digital Control System

10.5.2 Control Requirements

10.5.3 Notation of Variables

10.5.4 Calculation of Reference Control Variables

10.6 Predictive Current Control of 2L-PGS-Converter-Based PMSG WECS

10.6.1 Generator-side Control Scheme

10.6.2 Control Algorithm

10.7 Predictive Current Control of 3L-PGS-Converter-Based PMSG WECS

10.7.1 Generator-side Control Scheme

10.7.2 Control Algorithm

10.8 Analysis of PMSG WECS Performance with PGS Converters

10.9 Other MPC Schemes for PMSG WECS

10.9.1 Predictive Power Control

10.9.2 Predictive Speed Control

10.10 Real-Time Implementation of MPC Schemes

10.11 Concluding Remarks

References

Chapter 11 Control of SCIG WECS with Voltage Source Converters

11.1 Introduction

11.2 Configuration of SCIG WECS with BTB Converters

11.2.1 SCIG WECS with LV BTB Converters

11.2.2 SCIG WECS with MV BTB Converters

11.3 Modeling of Squirrel-Cage Induction Generator

11.3.1 Equivalent Circuit of SCIG

11.3.2 Continuous-Time Dynamic Models of SCIG

11.3.3 Discrete-Time Dynamic Models of SCIG

11.4 Control of Squirrel-Cage Induction Generator

11.4.1 Field-Oriented Control

11.4.2 Direct Torque Control

11.5 Digital Control of BTB Converter-Based SCIG WECS

11.5.1 Block Diagram of Digital Control System

11.5.2 Calculation of Reference Control Variables

11.6 Predictive Current Control of BTB 2L-VSC-Based SCIG WECS

11.6.1 Generator-side Control Scheme

11.6.2 Grid-side Control Scheme

11.6.3 Control Algorithm

11.7 Predictive Torque Control of BTB NPC Converter-Based SCIG WECS

11.7.1 Generator-side Control Scheme

11.7.2 Grid-side Control Scheme

11.7.3 Control Algorithm

11.8 Real-Time Implementation of MPC Schemes

11.9 Concluding Remarks

References

Chapter 12 Control of DFIG WECS with Voltage Source Converters

12.1 Introduction

12.2 Configuration of DFIG WECS and Power Flow

12.2.1 Power Conversion Configuration

12.2.2 Power Flow in DFIG WECS

12.3 Control of Doubly Fed Induction Generator

12.3.1 Stator Flux-Oriented Control

12.3.2 Stator Voltage-Oriented Control

12.4 Modeling of Doubly Fed Induction Generator

12.4.1 Equivalent Circuit of DFIG

12.4.2 Correlation Between Rotor Currents and Control Requirements

12.4.3 Continuous-Time Dynamic Models of DFIG

12.4.4 Discrete-Time Dynamic Models of DFIG

12.5 Digital Control of BTB Converter-Based DFIG WECS

12.5.1 Block Diagram of Digital Control System

12.5.2 Calculation of Reference Control Variables

12.6 Indirect Predictive Current Control of DFIG WECS

12.6.1 Generator-side Control Scheme

12.6.2 Grid-side Control Scheme

12.6.3 Control Algorithm

12.7 Direct Predictive Current Control of DFIG WECS

12.8 Concluding Remarks

References

Appendix A Turbine and Generator Parameters

A.1 Notation of Generator Variables

A.2 Base Values

A.3 Per-Unit Values

A.4 Wind Turbine Parameters

A.5 Three-Phase Grid Parameters

A.6 Permanent Magnet Synchronous Generator Parameters

A.7 Squirrel-Cage Induction Generator Parameters

A.8 Doubly Fed Induction Generator Parameters

Appendix B Chapter Appendices

B.1 Appendix for Chapter 4

References

B.2 Appendix for Chapter 5

Appendix C MATLAB Demo Projects

Index

List of Tables

Chapter 1

Table 1.1

Table 1.2

Table 1.3

Table 1.4

Table 1.5

Table 1.6

Chapter 2

Table 2.1

Table 2.2

Chapter 3

Table 3.1

Table 3.2

Chapter 4

Table 4.1

Table 4.2

Table 4.3

Table 4.4

Table 4.5

Table 4.6

Chapter 5

Table 5.1

Table 5.2

Table 5.3

Table 5.4

Table 5.5

Table 5.6

Table 5.7

Table 5.8

Chapter 6

Table 6.1

Chapter 7

Table 7.1

Table 7.2

Table 7.3

Table 7.4

Chapter 8

Table 8.1

Table 8.2

Chapter 9

Table 9.1

Chapter 10

Table 10.1

Table 10.2

Table 10.3

Table 10.4

Table 10.5

Table 10.6

Table 10.7

Table 10.8

Chapter 11

Table 11.1

Chapter 12

Table 12.1

Guide

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ABOUT THE AUTHORS

Venkata Yaramasu was born in Karumanchi, Guntur, India. He received his B.Tech degree in electrical and electronics engineering from Jawaharlal Nehru Technological University, Hyderabad, India, in 2005, an M.E. degree in electrical engineering with specialization in power electronics from S. G. S. Institute of Technology and Science, Indore, India, in 2008, and Ph.D. degreein electrical engineering from Ryerson University, Toronto, Canada, in 2014. During 2014–2015, he worked as a Postdoctoral Research Fellow at the Laboratory for Electric Drive Applications and Research (LEDAR) and Center for Urban Energy (CUE), Ryerson University. He is currently working as an Assistant Professor of Electrical Engineering in the School of Informatics, Computing, and Cyber Systems (SICCS), Northern Arizona University, Flagstaff, Arizona, USA. His research interests include renewable energy, high-power converters, variable-speed drives, electric vehicles, power quality, energy storage, smartgrid, and model predictive control.

Dr. Yaramasu worked closely with Rockwell Automation, Toronto Hydro, Hydro One, Natural Sciences and Engineering Research Council of Canada (NSERC), Wind Energy Strategic Network (WESNet) and Connect Canada, and completed 8 industrial projects in Power Electronics, Electric Drives, and Renewable Energy. He has published more than 50 peer-reviewed technical papers including 22 journal papers. He has produced more than 10 technical reports for the industry.

Dr. Yaramasu received six Best Student Paper Awards and two first prizes in National Level Technical Quiz Competitions during his undergraduate studies in India. He is a recipient of a Second Prize Paper Award from the IEEE Journal of Emerging and Selected Topics in Power Electronics (JESTPE) in 2015. During his Ph.D. studies at Ryerson University, he received Best Poster Awards from the Electrical and Computer Engineering (ECE) Department and Faculty of Engineering and Architectural Science (FEAS) in 2013, Student Research Awards from the Toronto Hydro, Hydro One, and Connect Canada in 2010, 2012, and 2013, Research Excellence Awards from the ECE Department in 2012, 2013, and 2014, a Best Poster Award at the NSERC-WESNet Annual Meeting 2010, and a Best Teaching Assistant Award from the FEAS in 2010.

Bin Wu graduated from Donghua University, Shanghai, China in 1978, and received his M.A.Sc. and Ph.D. degrees in electrical and computer engineering from the University of Toronto, Canada in 1989 and 1993, respectively. After being with Rockwell Automation Canada from 1992 to 1993, he joined Ryerson University, where he is currently a Professor in the Department of Electrical and Computer Engineering and a Senior NSERC/Rockwell Industrial Research Chair (IRC) in Power Electronics and Electric Drives.

Dr. Wu has published more than 350 peer-reviewed technical papers and two Wiley-IEEE Press books, and he holds more than 30 issued and pending patents in power electronics, adjustable-speed drives, and renewable energy systems. Dr. Wu is the founder of the Laboratory for Electric Drive Applications and Research (LEDAR), which has been recognized as the most advanced research facility of its kind in a Canadian university.

Dr. Wu has worked closely with Canadian companies and assisted them in achieving technical and commercial success through research and innovation. He has authored/coauthored more than 200 technical reports. Some of his inventions and patents have been adopted by industry and implemented in the production line, resulting in significant economic benefits.

Dr. Wu received the Gold Medal of the Governor General of Canada in 1993, the Premier’s Research Excellence Award in 2001, the NSERC Synergy Award for Innovation in 2002, the Ryerson Distinguished Scholar Award in 2003, the Ryerson FEAS Research Excellence Award in 2007, the Ryerson YSGS Outstanding Contribution to Graduate Education Award and the Professional Engineers Ontario (PEO) Engineering Excellence Medal in 2014. He is a fellow of Institute of Electrical and Electronics Engineers (IEEE), Engineering Institute of Canada (EIC), and Canadian Academy of Engineering (CAE). Dr. Wu is a Registered Professional Engineer in the Province of Ontario, Canada.

PREFACE

Due to depleting fossil fuels and growing environmental concerns on global warming, electricity production from renewable energy sources has received increasing attention in recent years. Among the renewableenergy sources, wind energy is rapidly becoming mainstream and competitive with conventional sources of energy. Wind energy installed capacity has increased exponentially over the past three decades and has become a real alternative to boost renewable energy penetration into the energy mix. The wind energy industry has experienced considerable technological advancements in terms of aerodynamic design, mechanical systems, electric generators, power electronic converters, control theory, and power system integration. Electric generators, power electronic converters, and control theory are the three important elements to enable the safe, reliable, and high-performance operation of wind energy conversion systems (WECS) while complying with the stringent grid code requirements.

In recent years, with the technological advancements in digital signal processors, the model predictive control (MPC) strategy has emerged as a simple and promising digital control tool in power electronics, variable-speed motor drives, and energy conversion systems. The MPC is a nonlinear control method and provides an approach that is better suited for controlling power converters in WECS. This method also mitigates several technical and operational disadvantages associated with classical control techniques, particularly during the low-switching frequency operation needed by the megawatt (MW)-level energy conversion systems. The MPC is attractive for controlling fast varying electrical variables because of its simple and intuitive concept, digital controller friendliness, finite number of optimizations, elimination of proportional-integral (PI) controllers, pulse-width-modulator-free structure, fast dynamic response, good steady-state performance during all operating conditions, capability to compensate perturbations and dead times of power conversion system, ease in incorporating nonlinearities and limitations in the design, and improved treatment of multivariable control problems with decoupling. Over the past decade, several books on power converters, wind energy systems, and MPC have been published. However, books that provide comprehensive analysis by combining these three important subject matters are unavailable. The proposed book deals with the MPC of power converters employed in a wide variety of variable-speed WECS. This book will not only fill the gap in the book market, but will also provoke further studies in the academe and industry for applications to other power electronic converters, adjustable-speed motor drives, and renewable energy conversion systems.

This book covers a wide range of topics on power converters, wind energy conversion, and MPC from the electrical engineering aspect. The contents of this book includes an overview of wind energy system configurations, power converters for variable-speed WECS, digital control techniques, MPC, modeling of power converters and wind generators for MPC design. Other topics include the mapping of continuous-time models to discrete-time models by various exact, approximate, and quasi-exact discretization methods, modeling and control of wind turbine grid-side two-level and multilevel voltage source converters. The authors also focus on the MPC of several power converter configurations for full variable-speed permanent magnet synchronous generator (PMSG)-based WECS, squirrel-cage induction generator (SCIG)-based WECS, and semi-variable-speed doubly fed induction generator (DFIG)-based WECS. By reflecting the latest technologies in the field, this book is a valuable reference for academic researchers, practicing engineers, and other professionals. It can also be used as a textbook or reference book for graduate-level and advanced undergraduate courses.

ORGANIZATION OF BOOK CONTENTS

This book contains 3 parts with 12 chapters, as illustrated in Figure 0.1. The flow of contents and interconnection between chapters is also described.

Part I is composed of four introductory-level chapters related to the power conversion and digital control of WECS. Chapter 1 provides an overview of high-power WECS, grid code requirements (e.g., fault-ride through and reactive power generation for wind power grid integration), electric generators, power electronics, wind energy configurations, WECS control, maximum power point tracking (MPPT) techniques, and finite control-set MPC (FCS-MPC). Chapter 2 reviews the state-of-the-art generator-converter configurations for variable-speed (Type 3 and 4) WECS in four categories with low-voltage (LV) and medium-voltage (MV) subcategories: (1) back-to-back (BTB) connected power converters, (2) passive generator-side (PGS) power converters, (3) converters for six-phase and open-winding generators, and (4) power converters without an intermediate DC link (matrix converters). Chapter 3 presents an overview of state-of-the-art digital control techniques including hysteresis control, linear control with PI regulator and modulation stage, sliding mode control, fuzzy logic control, artificial neural network-based control, dead-beat predictive control, and FCS-MPC by considering a case study of load current control. Chapter 4 discusses the fundamentals of MPC including its operating principle, step-by-step design procedure, cost function flexibility, weighting factor selection, control delay compensation, reference variable extrapolation, and minimum sampling time selection.

Part II contains three intermediate-level chapters on the modeling of power converters and wind generators to assist the implementation of MPC strategies for variable-speed WECS. Chapter 5 addresses the modeling of power converters employed in variable-speed WECS. The relationship between the input and output variables of a 2L-VSC, three-level (3L) neutral-point clamped converter, 3L flying capacitor converter, current source converter, direct matrix converter, and indirect matrix converter is formulated in terms of converter switching states. Chapter 6 deals with the state-space continuous-time modeling of PMSG, SCIG, and DFIG usedin Type 3 and 4 WECS. Chapter 7 introduces sampled-data models for MPC design. The exact discretization by the zero-order hold method, approximate discretization by forward Euler, backward Euler, and bilinear transformation, and quasi-exact discretization by matrix factorization and truncated Taylor series are discussed in detail with the help of example problems.

Figure 0.1 Organization of parts and chapters in this book.

Part III is composed of five advanced-level chapters with the MPC of variable-speed WECS. Chapter 8 presents the MPC strategy for grid-side converters (GSCs) for highpower LV and MV WECS. The synchronous- and stationary-frame predictive current control (PCC) and predictive power control (PPC) for 2L and 3L GSCs are analyzed in detail in terms of design steps, control algorithms, and case studies. This chapter serves as a basic building block for the complete digital control systems in Chapters 9 to 12. Chapter 9 discusses the MPC strategy for BTB-connected 2L- and 3L-VSC-based PMSG WECS. The zero d-axis current control and maximum torque per ampere control of surface mount and inset PMSGs are outlined. The calculation of reference control variables based on optimal tip-speed ratio and optimal torque MPPT algorithms are discussed. The PCC and predictive torque control (PTC) schemes are analyzed in detail. Chapter 10 provides a comprehensive analysis on the PGS converters employed in LV and MV PMSG WECS. The control requirements such as MPPT, balancing of DC-link capacitors voltage, regulation of net DC-bus voltage, and grid reactive power control are analyzed with 2L and 3L boost converters, as well as PCC and PPC schemes. Chapter 11 emphasizes the predictive control of BTB VSC for variable-speed SCIG-based LV and MV WECS. A step-by-step design of PCC and PTC schemes for 2L- and 3L-VSC-based SCIG WECS is presented, in addition to flowcharts, MATLAB programming, and case studies. Chapter 12 deals with the control of 2L-VSC-based semi-variable-speed (±30%) DFIG WECS. The indirect and direct rotor current dynamic models in discrete time are developed to realize the PCC schemes for DFIG.

The Appendix covers the following: 750-kW and 3.0-MW wind turbine parameters; low-, medium-, and high-speed PMSG parameters; SCIG and DFIG parameters; 750-kVA and 3.0-MVA GSC parameters; chapter appendices and details of the MATLAB demo files.

SALIENT FEATURES

In summary, this book is a unique and comprehensive work that deals with the electrical and control aspects of various WECS. We developed 242 figures, 42 tables, 18 example problems, 21 case studies, and 12 algorithms in the main body of the book to effectively transfer our knowledge to the readers. Furthermore, this book has the following features:

Reflects the latest technologies in power conversion and advanced control of WECS.

Presents the most comprehensive analysis on a wide variety of practical WECS. Illustrates important concepts with case studies, simulations, and experimental results.

Provides digital control design guidance with tables, charts, and graphs.

Presents a step-by-step procedure for the development of control schemes for various wind turbine configurations.

Analyzes continuous- and discrete-time modeling of various generators and power converters. This information can be used with other classical and advanced control schemes.

Presents a detailed analysis on weighting factor selection, which will fill the gap in current literature.

Discusses several discretization methods and extrapolation techniques.

Discusses real-time implementation issues such as the configuration of prototype converters, selection of sampling time, and compensation of control delay.

Presents useful material for other power electronic applications such as adjustable-speed motor drives, power quality conditioners, electric vehicles, photovoltaic energy systems, distributed generation, and high-voltage direct current transmission.

Provides

S-Function Builder

programming in MATLAB environment to implement various MPC strategies.

Supplies

MATLAB

demo files for quick-start on MPC design and simulation.

Serves as a valuable reference for academic researchers, practicing engineers, and other professionals.

Provides adequate technical background for graduate- and undergraduate-level teaching.

VENKATA YARAMASU

BIN WU

April 2016

ACKNOWLEDGMENTS

This book has been written as a result of many years of our research on wind energy and model predictive control. The manuscript took almost two and half years to complete. We would like to thank our colleagues and friends who have supported and helped us in this endeavor. The references section of each chapter also acknowledges the research work of various scholars who have been passionate about this research area.

We would like to acknowledge the valuable support of Mr. Apparao Dekka, Ph.D. student in Laboratory for Electric Drive Applications and Research at the Ryerson University, in developing the figures for Chapters 7, 8, 11, and 12. His help with the MATLAB simulations for Chapters 11 and 12 is highly appreciated. We are indebted to Mr. Tomasz Sidelko, double degree Master’s student with Wroclaw University and Ryerson University, for devoting significant amount of time to develop high-quality artwork and figures during the initial phase of this book. We wish to thank Drs. Jose Rodriguez, Marco Rivera, Samir Kouro, Salvador Alepuz, and Paresh C. Sen for the collaborative works on wind energy and model predictive control.

We are also very thankful to the reviewers for painstakingly reviewing our book proposal and final manuscript and providing us constructive comments to improve the quality and readability of the book. We very much appreciate Mr. Samkruth Aluru, Master’s student at Northern Arizona University and Dr. Sebastian Rivera, Postdoctoral Fellow at University of Toronto for proofreading the final manuscript.

Our special thanks to the Wiley/IEEE press editors Mary Hatcher, Brady Chin, and Tim Pletscher for their help in the preparation of this manuscript. We are also thankful to the Wiley production team members for guiding us to prepare camera-ready copy of this manuscript. We express our intense gratitude to our families and friends who supported and inspired us in every possible way to see the completion of this work.

V. Y.

B. W.

This book is developed as an outgrowth of my Ph.D. dissertation entitled “Predictive Control of Multilevel Converters for Megawatt Wind Energy Conversion Systems.” I am thankful to Drs. Dewei Xu and Amir Yazdani at Ryerson University for their encouragement in transforming my Ph.D. dissertation into a book. I express my sincere gratitude to my former Ph.D. dissertation supervisor, Dr. Bin Wu, for his guidance in writing this manuscript. This book would not have been envisaged without his help.

V. Y.

ACRONYMS

2L

Two-Level (Converter)

3L

Three-Level (Converter)

1S

Single-Stage (Gearbox)

2S

Two-Stage (Gearbox)

3S

Three-Stage (Gearbox)

3

ϕ

Three-Phase (Generator/Grid)

AC

Alternating Current

ADC

Analog-to-Digital Conversion

ANPC

Active Neutral-Point Clamped

BTB

Back-to-Back

CHB

Cascaded H-Bridge

CMV

Common-Mode Voltage

COE

Cost of Energy

CSC

Current Source Converter

CT

Continuous-Time

DAC

Digital-to-Analog Conversion

DBPC

Deadbeat Predictive Control

DC

Direct Current

DCC

Diode-Clamped Converter

DD

Direct-Driven

DFIG

Doubly Fed Induction Generator

DFOC

Direct Field-Oriented Control

DG

Distributed Generation

DMC

Direct Matrix Converter

DPC

Direct Power Control

DSO

Distribution System Operator

DSP

Digital Signal Processor

DT

Discrete Time

DTC

Direct Torque Control

E+P

Estimation + Prediction

FC

Flying Capacitor

FCS-MPC

Finite Control-Set Model Predictive Control

FFT

Fast Fourier Transform

FOC

Field-Oriented Control

FPGA

Field-Programmable Gate Array

FRT

Fault Ride-Through

FSWT

Fixed-Speed Wind Turbine

GCT

Gate-Controlled Thyristor

GSC

Grid-side Converter

GSF

Generator Signal Feedback

GW

Gigawatt

HAW

Horizontal-Axis Wind Turbine

HTS

High-Temperature Superconducting

HVAC

High-Voltage Alternating Current

HVDC

High-Voltage Direct Current

HVRT

High-Voltage Ride-Through

IFOC

Indirect Field-Oriented Control

IG

Induction Generator

IGBT

Insulated Gate Bipolar Transistor

IGCT

Integrated Gate-Commutated Thyristor

IM

Induction Machine

IMC

Indirect Matrix Converter

IPMSG

Interior (Inset) Permanent Magnet Synchronous Generator

LPF

Low-Pass Filter

LTI

Linear Time-Invariant

LTV

Linear Time-Variant

LV

Low Voltage

LVRT

Low-Voltage Ride-Through

MIPS

Million Instructions Per Second

MMC

Modular Multilevel Converter

MMMC

Multi-Modular Matrix Converter

MPC

Model Predictive Control

MPP

Maximum Power Point

MPPT

Maximum Power Point Tracking

MSC

Machine-side Converter

MTPA

Maximum Torque Per Ampere

MV

Medium Voltage

MW

Megawatt

NPC

Neutral-Point Clamped

OT

Optimal Torque

OTSR

Optimal Tip-Speed Ratio

PCC

Point of Common Coupling

PCC

Predictive Current Control

PDPC

Predictive Direct Power Control

PDVC

Predictive DC-Bus Voltage Control

PF

Power Factor

PGS

Passive Generator-side

P+P

Prediction + Prediction

P+P

2

Prediction + Double Prediction

PPC

Predictive Power Control

PSC

Predictive Speed Control

PSF

Power Signal Feedback

PTC

Predictive Torque Control

PVC

Predictive Voltage Control

PI

Proportional-Integral

PLL

Phase-Locked Loop

PMSG

Permanent Magnet Synchronous Generator

PWM

Pulse Width Modulation

RL

Resistive-Inductive

RMS

Root Mean Square

RPG

Reactive Power Generation

RSC

Rotor-side Converter

SCIG

Squirrel Cage Induction Generator

SFOC

Stator Flux-Oriented Control

SG

Synchronous Generator

SGCT

Symmetrical Gate-Controlled Thyristor

SHE

Selective Harmonic Elimination

SPMSG

Surface-Mount Permanent Magnet Synchronous Generator

SRF

Synchronous Reference Frame

STATCOM

Static Synchronous Compensator

SVC

Static VAR Compensator

SVM

Space Vector Modulation

SVOC

Stator Voltage-Oriented Control

TDD

Total Demand Distortion

THD

Total Harmonic Distortion

TSO

Transmission System Operator

TSR

Tip-Speed Ratio

UPF

Unity Power Factor

VAWT

Vertical-Axis Wind Turbine

VOC

Voltage-Oriented Control

VSC

Voltage Source Converter

VSI

Voltage Source Inverter

VSR

Voltage Source Rectifier

VSWT

Variable-Speed Wind Turbine

WECS

Wind Energy Conversion Systems

WF

Wind Farm

WFCP

Wind Farm Collection Point

WRIG

Wound Rotor Induction Generator

WRSG

Wound Rotor Synchronous Generator

WT

Wind Turbine

WTPC

Wind Turbine Power Curves

ZDC

Zero

d

-axis Current

ZOH

Zero-Order Hold

ZVRT

Zero-Voltage Ride-Through

SYMBOLS

Notation

P, Q

Active and reactive power

R, L, C

Resistance, inductance, and capacitance

υ

,

i, ψ

Voltage, current, and flux linkage (

peak

values)

V

,

I

,

Ψ

Voltage, current, and flux linkage (

rms

values)

s

Switching signal

Superscripts for variable x

x

op