Power Electronics and Energy Conversion Systems, Fundamentals and Hard-switching Converters, Volume 1
Volume 1. Fundamentals and hard-switching converters
Power Electronics and Energy Conversion Systems Series

Power Electronics and Energy Conversion Systems is a definitive five-volume reference spanning classical theory through practical applications and consolidating the latest advancements in energy conversion technology. Comprehensive yet highly accessible, each volume is organised in a basic-to-sophisticated crescendo, providing a single-source reference for undergraduate and graduate students, researchers and designers.

Volume 1 Fundamentals and Hard-switching Converters introduces the key challenges in power electronics from basic components to operation principles and presents classical hard- and soft-switching DC to DC converters, rectifiers and inverters. At a more advanced level, it provides comprehensive analysis of DC and AC models comparing the available approaches for their derivation and results. A full treatment of DC to DC hard-switching converters is given, from fundamentals to modern industrial solutions and practical engineering insight. The author elucidates various contradictions and misunderstandings in the literature, for example, in the treatment of the discontinuous conduction operation or in deriving AC small-signal models of converters.

Other key features:
? Consolidates the latest advancements in hard-switching converters including discontinuous capacitor voltage mode, and their use in power-factor-correction applications
? Includes fully worked design examples, exercises, and case studies, with discussion of the practical consequences of each choice made during the design
? Explains all topics in detail with step-by-step derivation of formulas appropriate for energy conversion courses
? End-of-section review of the learned material
? Includes topics treated in recent journal, conference and industry application coverage on solutions, theory and practical concerns

With emphasis on clear explanation, the text offers both a thorough understanding of DC to DC converters for undergraduate and graduate students in power electronics, and more detailed material suitable for researchers, designers and practising engineers working on the development and design of power electronics. This is an accessible reference for engineering and procurement managers from industries such as consumer electronics, integrated circuits, aerospace and renewable energy.

Preface xv

1 Introduction 1

1.1 Why Energy Conversion Electronics Circuits? 1

1.1.1 Applications in the Information and Telecommunication Industry 2

1.1.2 Applications in Renewable Energy Conversion 4

1.1.3 Future Energy Conversion – Fuel Cells 6

1.1.4 Electric Vehicles 6

1.1.5 Applications in Electronic Display Devices 8

1.1.6 Audio Amplifiers 9

1.1.7 Applications in Portable Electronic Devices 9

1.1.8 Applications in High Voltage Physics Experiments and Atomic Accelerators 10

1.1.9 Lighting Technology 11

1.1.10 Aerospace Applications 11

1.1.11 Power System Conditioning 12

1.1.12 Energy Recycling in Manufacturing Industry 12

1.1.13 Applications in Space Exploration 12

1.1.14 Defense Applications 14

1.1.15 Drives and High-Power Industrial Applications 15

1.1.16 Classification of Power Electronic Circuits 15

1.2 Basic Principles of Operation of a Power Electronics Circuit 17

1.3 Basic Components of the Power Circuit: Power Semiconductor Switches and Passive Reactive Elements 28

1.3.1 Uncontrollable Switches – Power Diodes 28

1.3.2 Semicontrollable Switches (Thyristors) 32

1.3.3 Controllable Switches 35

1.3.4 Gallium Nitride (GaN) Switch Technology 51

1.3.5 Energy Losses Associated with Power Switches 52

1.3.6 Passive Reactive Elements 65

1.3.7 Ultracapacitors 80

1.4 Basic Steady-State Analysis of Duty Cycle Controlled Converters with Constant Switching Frequency 81

1.4.1 Input-to-Output Voltage Ratio for Basic DC-DC Converters 81

1.4.2 Continuous and Discontinuous Conduction Operation Modes 85

1.4.3 Design of the Elements of the Basic Converters 85

1.4.4 Controller for Duty Cycle Control (PWM) 88

1.4.5 Conversion Efficiency, Hard-switching and Soft-switching 92

1.5 Introduction to Switched-Capacitor (SC) Converters 96

1.6 Frequency-Controlled Converters 101

1.6.1 Resonant Converters 101

1.6.2 Quasi-Resonant Converters (QRC) 110

1.7 Overview on AC-DC Rectifiers and DC-AC Inverters 119

1.7.1 Rectifiers 119

1.7.2 Inverters 132

1.8 Case Studies 140

1.8.1 Case Study 1 140

1.8.2 Case Study 2 146

1.8.3 Case Study 3 150

1.9 Highlights of the Chapter 154

Problems 155

Bibliography 157

2 Modeling DC-DC Converters 161

2.1 What is the Purpose of Modeling the Power Stage? 162

2.2 Average State-Space Equations, Small-Ripple Approximation (Time-Linearization) 164

2.3 DC Voltage Gain and AC Small-Signal Open-Loop Transfer Functions Based on Average State-Space Equations for Converters Operating in Continuous Conduction Mode 169

2.3.1 DC Voltage Gain and AC Open-Loop Line-to-Load Voltage Transfer Function 169

2.3.2 Duty Cycle-to-Output Voltage AC Transfer Function. Small-Signal Approximation 171

2.3.3 DC Gain and AC Small-Signal Open-Loop Transfer Functions of the Boost, Buck and Buck-Boost Converters Operating in CCM 173

2.3.4* Graphical Averaged Models of the Boost, Buck and Buck-Boost Converters Operating in CCM 191

2.3.5* Canonical Graphical Averaged Models of DC-DC Converters Operating in CCM 211

2.4 DC Voltage Gain and AC Small-Signal Open-Loop Transfer Functions Based on Average State-Space Equations for Converters Operating in Discontinuous Conduction Mode 217

2.4.1 Reduced-Order Averaged Models 217

2.4.2* Full-Order Averaged Models 237

2.5* Average PWM Switch Model 253

2.5.1 Average PWM Switch Model for Converters Operating in Continuous Conduction Mode 253

2.5.2 Average PWM Switch Model for Converters Operating in Discontinuous Conduction Mode 263

2.6 Average Model of the Switches Resistances and Diode Forward Voltage. Average Model of the PWM 288

2.6.1 Average Model of the Switches DC Resistances and Diode Forward Voltage 288

2.6.2 Average Model of the PWM 291

2.7* Average Resonant Switch Model for the DC and Small-Signal Analysis of QRC Converters 292

2.7.1 Average Model of the Zero-Current (ZC) Resonant Switch 293

2.7.2 Average Model of the Zero-Voltage (ZV) Resonant Switch 300

2.7.3 DC Analysis and Open-Loop Small-Signal Transfer Functions of ZCS Quasi-Resonant Converters 305

2.7.4 DC Analysis and Open-Loop Small-Signal Transfer Functions of ZVS Quasi-Resonant Converters 325

2.8 Simulation and Computer-Aided Design of Power Electronics Circuits 339

2.9 Case Study 355

2.10 Highlights of the Chapter 362

Problems 365

Bibliography 368

3 Classical DC-DC PWM Hard-switching Converters 369

3.1 Buck DC-DC PWM Hard-switching Converter 369

3.1.1 Influence of the DC Resistance of the Inductor 369

3.1.2 Boundary Control 375

3.1.3 Calculation of Losses in a Buck Converter Operating in CCM by Considering the Inductor Current Ripple and the ESR of the Capacitor 377

3.1.4 Design of a Buck Converter in CCM Operation 382

3.1.5 Buck Converter with Input Filter 386

3.1.6 Review of the Steady-State Analysis of the Buck Converter in DCM Operation 390

3.1.7 Design of a Buck Converter in DCM Operation 395

3.1.8* Aspects of Dynamic Response of Buck Converter 399

3.2 Boost DC-DC PWM Hard-switching Converter 402

3.2.1 Boost Converter in Steady-State CCM Operation 402

3.2.2 Boost Converter in Steady-State DCM Operation 410

3.2.3* Aspects of Dynamic Response of Boost Converter 417

3.3 Buck-Boost DC-DC PWM Hard-switching Converter 420

3.3.1 Buck-Boost Converter in Steady-State CCM Operation 421

3.3.2 Buck-Boost Converter in Steady-State DCM Operation 429

3.3.3* Aspects of Dynamic Response of Buck-Boost Converter 437

3.4 Cuk (Boost-Buck) PWM Hard-switching Converter 437

3.4.1 Derivation and Switching Operation of the Cuk Converter 438

3.4.2 Steady-State Analysis of Cuk Converter in CCM Operation and its Design 438

3.4.3* DC Voltage Gain and AC Small-Signal Characteristics of theCuk Converter in the Presence of Parasitic Resistances 447

3.4.4 Design Example and Commercially Available Cuk Converters 455

3.4.5* Discontinuous Conduction Mode for the Cuk Converter 456

3.4.6* Cuk Converter with Coupled Inductor 468

3.5 SEPIC PWM Hard-switching Converter 470

3.5.1 SEPIC Converter in CCM Operation 471

3.5.2 Steady-State Analysis of SEPIC Converter in CCM Operation 473

3.5.3* Small-Signal Analysis of the SEPIC Converter in CCM Operation 479

3.5.4 Commercially Available SEPIC Converters: Case Studies 483

3.5.5* SEPIC Converter in DCM Operation 489

3.5.6* AC Analysis of SEPIC Converter in DICM 500

3.5.7* Isolated SEPIC Converter 503

3.6 Zeta (Inverse SEPIC) PWM Hard-switching Converter 503

3.6.1 Zeta Converter in CCM Operation 504

3.6.2 Steady-State Analysis of a Zeta Converter in CCM Operation 505

3.6.3* Small-Signal Analysis of the Zeta Converter in CCM Operation 514

3.6.4 Design Example and Case Study 515

3.6.5* Zeta Converter in DCM Operation 520

3.6.6* Isolated Zeta Converter 529

3.7 Forward Converter 530

3.7.1 The Role of a High-Frequency Transformer in the Structure of DC-DC Converters 530

3.7.2 Derivation of Forward Converter 531

3.7.3 Operation of Forward Converter in CCM 534

3.7.4 Operation of a Forward Converter in DCM and Design Considerations for CCM and DCM 545

3.7.5* Multiple-Output Forward Converter 551

3.7.6* Other Core Reset Strategies 551

3.7.7 Examples of Practical Designs: Case Studies 564

3.8* Isolated Cuk Converter 568

3.9 Flyback Converter 574

3.9.1 Derivation of the Flyback Converter 574

3.9.2 Operation of Flyback Converter in CCM and DCM 577

3.9.3 Effects of the Coupled Inductor Leakage Inductance 587

3.9.4* Small-Signal Model of the Flyback Converter 598

3.9.5 Designs of the Flyback Converter: Case Studies – Practical Considerations 600

3.10 Push–Pull Converter 607

3.10.1 Push–Pull Converter of Buck Type (Voltage Driven) 607

3.10.2 CCM Operation of the Push–Pull Converter 608

3.10.3 Non-Idealities in the Push–Pull Converter 616

3.10.4 DCM Operation 619

3.10.5* Push–Pull Converter of the Boost Type (Current Driven) 625

3.10.6 Design Example 631

3.11 Half-Bridge Converter 634

3.11.1 The Buck-Type Half-Bridge Topology 634

3.11.2 CCM Operation 636

3.11.3 Input-to-Output Voltage Conversion Ratio and Design of a Half-Bridge Converter in CCM Operation 645

3.11.4 Practical Aspects 647

3.11.5 DCM Operation 648

3.11.6* Current-Driven Half-Bridge Converter 652

3.12 Full-Bridge Converter 657

3.12.1 Full-Bridge Topology 657

3.12.2 CCM Operation of the Buck-Type Full-Bridge Converter 660

3.12.3 Input-to-Output Voltage Conversion Ratio and Design of a Buck-Type Full-Bridge Converter in CCM Operation 672

3.12.4 Practical Aspects 676

3.12.5* Other Transistor Control Schemes: Phase-Shift Control 676

3.12.6* Current-Driven Full-Bridge Converter 680

3.13 Highlights of the Chapter 687

Problems 696

Bibliography 702

4 Derived Structures of DC-DC Converters 705

4.1 Current Doubler Rectifier (CDR) for Push–Pull, Half-Bridge and Full-Bridge Converters 705

4.1.1 Cyclical Operation of Current Doubler Rectifier 706

4.1.2 Voltage Conversion Ratio of Converters with CDR 711

4.1.3 Ripple Cancellation in the Output Current 711

4.1.4* Other Structures of CDR 713

4.1.5 Penalties of CDR 719

4.1.6* Current Tripler and Current Multiplier 719

4.2 Voltage Doubler and Voltage Multiplier Rectifier 721

4.2.1 Full-Wave Bridge Voltage Doubler 721

4.2.2 Greinacher Multiplier 723

4.2.3 Voltage Tripler and General Cockcroft–Walton Multiplier 727

4.2.4* Voltage Doubler with One Capacitor 729

4.2.5 Fibonacci Voltage Multiplier 730

4.2.6 Voltage Dividers 735

4.2.7* “Economy” Power Supply and the 48 Power Supply 736

4.3 Quadratic Converters 742

4.3.1 Quadratic Buck Converters 743

4.3.2* Buck-Boost Quadratic Converters (D<0.5) 746

4.4* Two-Switch Buck-Boost Converter 748

4.4.1 Buck-Boost Converters Obtained by Interleaving a Boost and a Buck Switching Cell 749

4.4.2 Z-Source Buck-Boost Converter with Positive Output Voltage 753

4.5* Switched-Capacitor/Switched-Inductor Integrated Basic Converters 757

4.5.1 Family of Converters Based on Switched-Capacitor/Switched-Inductor Structures 757

4.5.2 KY Converter 776

4.5.3 Watkins–Johnson Converter 782

4.6* The Sheppard–Taylor Converter 783

4.6.1 CCM Operation 783

4.6.2 Discontinuous Conduction Mode Operation 785

4.6.3 Isolated Sheppard–Taylor Converter 791

4.7* Converters with Low Voltage Stress on the Active Switches 793

4.7.1 Four-Switch Full-Bridge-Type Converter with Vin/2 Primary-Side Switches Voltage Stress 794

4.7.2 Converter with Vin/3 Voltage Stress on the Primary-Side Switches 797

4.7.3 Three-Level Boost Converter 797

4.8* Tapped Inductor-Based Converters 805

4.8.1 Tapped Inductor Buck Converter and VRMs (Voltage Regulator Module) 805

4.8.2 Tapped Inductor Boost Converter 812

4.9* Current-Driven Dual-Bridge Converter with Center-Tapped Inductor 812

4.10 Highlights of the Chapter 824

Problems 829

Bibliography 830

Index 833

Professor Adrian Ioinovici, Electrical and Electronics Engineering Department, Holon Institute of Technology, Israel Professor Adrian Ioinovici joined the Holon Institute of Technology in 1982; prior to this he was a Professor in the Electrical Engineering Department at Hong Kong Polytechnic University. He has been Chairman of the Technical Committee on Power Systems and Power Electronics of the IEEE Circuits and Systems Society. He has served as an Associate Editor of the IEEE Transactions on Circuits and Systems-I, and of the Journal of Circuits, Systems and Computers. He was co-chairman of the Tutorial Committee at ISCAs’06 and designed co-chair, Special Session Committee at ISCAS’10 in Paris.

Professor Ioinovici is the author of the book Computer-Aided Analysis of Active Circuits (New York: Marcel Dekker, 1990) and of the chapter "Power Electronics" in the Encyclopedia of Physical Science and Technology (Acad. Press, 2001). He has published more than 150 papers in circuit theory and power electronics, his research intersts being in simulation of power electronics circuits, switched-capacitor-based converters and inverters, soft-switching DC power supplies, and three-level converters.