Pulsewidth Modulated DC-to-DC Power Conversion: Circuits, Dynamics, Control, and DC Power Distribution Systems, 2nd Edition
- Length: 720 pages
- Edition: 2
- Language: English
- Publisher: Wiley-IEEE Press
- Publication Date: 2021-10-19
- ISBN-10: 111945445X
- ISBN-13: 9781119454458
- Sales Rank: #4876574 (See Top 100 Books)
Explore a fully updated reference for professional and student engineers working with pulsewidth modulated DC-to-DC power conversion
The newly revised Second Edition of Pulsewidth Modulated DC-to-DC Power Conversion: Circuits, Dynamics, and Control Designs delivers a comprehensive exploration of pulsewidth modulated DC-to-DC converters for analysis and design as standalone converters and as an interconnected system. The book begins with discussions of the circuits, dynamics, and control of standalone PWM converters before moving on to examine the dynamic analysis and system design of DC power distribution systems.
The distinguished authors balance theory with the practical aspects of DC-to-DC power conversion based on classical linear system theory. They include new information on the generalization of power stage modeling, the Nyquist criterion, and universal small-signal models for PWM DC-to-DC converters. The book also includes supplemental material, like a solutions manual, lecture slides, and PSpice source codes for over 250 PSpice programs for illustrative simulations. Readers will also benefit from the inclusion of:
- A thorough introduction to PWM DC-to-DC power conversion, power stage components, and buck converters
- An exploration of DC-to-DC power converter circuits, including boost converters, three basic converters, and flyback converters
- Discussions of the modeling and dynamics of PWM converters, including power stage transfer functions and the dynamic performance of PWM DC-to-DC converters
- An examination of control schemes and converter performance, including closed-loop performance and feedback compensation
Perfect for senior undergraduate students in departments of electrical engineering or electronics, Pulsewidth Modulated DC-to-DC Power Conversion will also earn a place in the libraries of graduate students and practitioners of power electronics or electrical energy conversions, as well as analog/digital circuit engineers.
Cover Title Page Copyright Contents Author Biography Preface Chapter 1 PWM Dc‐to‐Dc Power Conversion 1.1 PWM Dc‐to‐Dc Power Conversion 1.1.1 Dc‐to‐Dc Power Conversion 1.1.2 PWM Technique 1.2 Standalone Dc‐to‐Dc Power Conversion System 1.2.1 Dc Source with Non‐ideal Characteristics 1.2.2 Dc‐to‐Dc Converter as Voltage Source 1.2.3 Load as Dynamic Current Sink 1.3 Features and Issues of PWM Dc‐to‐Dc Converter 1.3.1 Dc‐to‐Dc Power Converter Circuits 1.3.2 Dynamic Modeling and Analysis 1.3.3 Dynamic Performance and Control Design 1.4 Dc Power Distribution Systems 1.4.1 Structure of Dc Power Distribution Systems 1.4.2 Issues in Dc Power Distribution System Analysis and Design 1.5 Chapter Highlights 1.5.1 Part I: Dc‐to‐Dc Converter Circuits 1.5.2 Part II: Modeling and Dynamics of PWM Converters 1.5.3 Part III: Control Schemes and Converter Performance 1.5.4 Part IV: Dc Power Distribution Systems Part I Dc‐to‐Dc Power Converter Circuits Chapter 2 Buck Converter 2.1 Ideal Step‐Down Dc‐to‐Dc Power Conversion 2.2 Buck Converter: Step‐Down Dc‐to‐Dc Converter 2.2.1 Evolution to Buck Converter 2.2.2 Frequency‐Domain Analysis 2.3 Buck Converter in Start‐up Transient 2.3.1 Piecewise Linear Analysis 2.3.2 Start‐up Response 2.4 Buck Converter in Steady State 2.4.1 Circuit Analysis Techniques 2.4.1.1 Piecewise Linear Analysis 2.4.1.2 Small‐Ripple Approximation 2.4.1.3 Flux Linkage Balance Condition and Charge Balance Condition 2.4.2 Steady‐State Analysis 2.4.3 Evaluation of Output Voltage Ripple 2.4.3.1 Evaluation with Ideal Capacitor 2.4.3.2 Effects of Parasitic Resistance of Capacitor 2.5 Buck Converter in Discontinuous Conduction Mode 2.5.1 Origin of Discontinuous Conduction Mode Operation 2.5.2 Conditions for DCM Operation 2.5.3 Steady‐State Operation in DCM 2.6 Closed‐Loop Control of Buck Converter 2.6.1 Closed‐Loop Feedback Controller 2.6.1.1 Pulsewidth Modulation 2.6.1.2 Voltage Feedback Circuit 2.6.2 Transient Responses of Closed‐Loop Controlled Buck Converter 2.6.2.1 Step Input Response 2.6.2.2 Step Load Response 2.6.2.3 Operational Mode Change Response 2.7 Chapter Summary Problems Chapter 3 Dc‐to‐Dc Power Converter Circuits 3.1 Boost Converter 3.1.1 Evolution to Boost Converter 3.1.2 Steady‐State Analysis in CCM 3.1.2.1 Steady‐State Operation in CCM 3.1.2.2 Estimation of Output Voltage Ripple 3.1.3 Steady‐State Analysis in DCM 3.1.4 Effects of Parasitic Resistance on Voltage Gain 3.2 Buck/Boost Converter 3.2.1 Evolution to Buck/Boost Converter 3.2.2 Steady‐State Analysis in CCM 3.2.2.1 Steady‐State Operation in CCM 3.2.2.2 Estimation of Output Voltage Ripple 3.2.3 Steady‐State Analysis in DCM 3.3 Three Basic Converters 3.3.1 Structure and Operation of Three Basic Converters 3.3.2 Voltage Gain of Three Basic Converters 3.4 Flyback Converter: Transformer‐Isolated Buck/Boost Converter 3.4.1 Evolution to Flyback Converter 3.4.2 Steady‐State Analysis in CCM 3.4.3 Steady‐State Analysis in DCM 3.5 Bridge‐Type Buck‐Derived Isolated Dc‐to‐Dc Converters 3.5.1 Switch Network and Multi‐Winding Transformer 3.5.1.1 Switch Network Structure 3.5.1.2 Circuit Models for Multi‐winding Transformers 3.5.2 Full‐Bridge Converter 3.5.2.1 Operation with Ideal Transformer 3.5.2.2 Effects of Magnetizing Inductance 3.5.3 Half‐Bridge Converter 3.5.4 Push–Pull Converter 3.6 Forward Converters 3.6.1 Basic Operational Principles 3.6.1.1 Reset Problem and Reset Circuit 3.6.1.2 Switch Network with Zener Diode Reset 3.6.1.3 Switch Network with Tertiary Winding Reset 3.6.2 Tertiary‐Winding Reset Forward Converter 3.6.3 Two‐Switch Forward Converter 3.7 Chapter Summary Reference Problems Part II Modeling and Dynamics of PWM Converters Chapter 4 Modeling PWM Dc‐to‐Dc Converters 4.1 Overview of PWM Converter Modeling 4.1.1 Power Stage Modeling 4.1.2 PWM Block Modeling 4.1.3 Voltage Feedback Circuit and Small‐Signal Model of PWM Converter 4.2 Averaging Power Stage Dynamics 4.2.1 State‐Space Averaging Method 4.2.1.1 Switched State‐Space Model and Switching Function 4.2.1.2 Continuous Duty Ratio and Averaged State‐Space Model 4.2.2 Circuit Averaging Technique 4.2.2.1 Averaging Switch Drive Signal 4.2.2.2 Procedure of Circuit Averaging 4.2.2.3 PWM Switch 4.2.2.4 Averaging PWM Switch 4.2.2.5 Average Models for Three Basic PWM Converters 4.2.3 Circuit Averaging and State‐Space Averaging 4.3 Linearizing Averaged Power Stage Dynamics 4.3.1 Linearization of Nonlinear Function and Small‐Signal Model 4.3.1.1 Single‐Variable Nonlinear Functions 4.3.1.2 Multiple‐Variable Nonlinear Functions 4.3.2 Small‐Signal Model of PWM Switch – The PWM Switch Model 4.3.3 Small‐Signal Model of Converter Power Stage 4.4 Frequency Response of Converter Power Stage 4.4.1 Sinusoidal Response of Power Stage 4.4.2 Frequency Response and s‐domain Small‐Signal Model 4.5 Generalization of Power Stage Modeling 4.5.1 Power Stage Modeling with Parasitic Resistances 4.5.1.1 Buck Converter with Ideal Voltage Source 4.5.1.2 Buck Converter with Input Filter 4.5.1.3 Linearization of Averaged PWM Switch Equation 4.5.1.4 Predictions of Refined Small‐Signal Model 4.5.2 Modeling PWM Converters in DCM Operation 4.5.2.1 Averaged Equations for PWM Switch in DCM 4.5.2.2 Linearization of Averaged Equation and Small‐Signal Circuit Model 4.5.3 Modeling Isolated PWM Converters 4.5.3.1 Modeling Forward Converter and Bridge‐Type Converters 4.5.3.2 Modeling Flyback Converter 4.6 Small‐Signal Gain of PWM Block 4.7 Universal Small‐Signal Model for PWM Dc‐to‐Dc Converters 4.7.1 Voltage Feedback Circuit 4.7.1.1 Output Voltage Control 4.7.1.2 Voltage Feedback Compensation 4.7.2 Universal Small‐Signal Model for PWM Converters 4.8 Chapter Summary References Problems Chapter 5 Power Stage Transfer Functions 5.1 Bode Plot for Transfer Functions 5.1.1 Basic Definitions 5.1.1.1 Transfer Function 5.1.1.2 Frequency Response 5.1.1.3 Polar Plot and Bode Plot Representations 5.1.2 Bode Plots for Multiplication Factors 5.1.2.1 Constant 5.1.2.2 Single and Double Integration Functions 5.1.2.3 Single and Double Differentiation Functions 5.1.2.4 Single Pole and Single Zero Functions 5.1.2.5 Double Pole and Double Zero Functions 5.1.2.6 RHP Pole and RHP Zero Functions 5.1.3 Bode Plot Construction for Transfer Functions 5.1.3.1 Examples of Bode Plot Construction 5.1.3.2 Non‐minimum Phase System 5.1.4 Identification of Transfer Function from Bode Plot 5.2 Power Stage Transfer Functions of Three Basic Converters in CCM Operation 5.2.1 Power Stage Transfer Functions of Buck Converter 5.2.1.1 Input‐to‐Output Transfer Function 5.2.1.2 Duty Ratio‐to‐Output Transfer Function 5.2.1.3 Load Current‐to‐Output Transfer Function 5.2.2 Power Stage Transfer Functions of Boost Converter 5.2.2.1 Input‐to‐Output Transfer Function 5.2.2.2 Duty Ratio‐to‐Output Transfer Function and RHP Zero 5.2.2.3 Load Current‐to‐Output Transfer Function 5.2.2.4 Functional Origin of RHP Zero 5.2.3 Power Stage Transfer Functions of Buck/Boost Converter 5.3 Power Stage Transfer Functions in DCM Operation 5.3.1 Evaluation of DCM Transfer Functions 5.3.2 Analysis of DCM Duty Ratio‐to‐Output Transfer Function 5.4 Power Stage Transfer Functions of Isolated Converters 5.4.1 Tertiary‐Winding Reset Forward Converter 5.4.2 Flyback Converter 5.5 Empirical Methods for Small‐Signal Analysis 5.6 Chapter Summary Reference Problems Chapter 6 Dynamic Performance of PWM Dc‐to‐Dc Converters 6.1 Stability 6.2 Frequency‐Domain Performance Criteria 6.2.1 Loop Gain 6.2.2 Audio‐susceptibility 6.2.3 Output Impedance 6.3 Time‐Domain Performance Metrics 6.3.1 Step Load Response 6.3.2 Step Input Response 6.4 Stability of Dc‐to‐Dc Converters 6.4.1 Stability of Linear Time‐Invariant Systems 6.4.1.1 Definition of BIBO Stability 6.4.1.2 Unit Impulse Function and Impulse Response 6.4.1.3 Impulse Response and BIBO Stability 6.4.1.4 Pole Locations and BIBO Stability 6.4.2 Small‐Signal Stability of Dc‐to‐Dc Converters 6.5 Nyquist Criterion 6.5.1 Theoretical Foundation of Nyquist Criterion 6.5.1.1 Contour Mapping from s‐plane to F(s)‐plane 6.5.1.2 Cauchy's Theorem 6.5.2 Proof of Cauchy's Theorem 6.5.2.1 Proof of Fact I and Fact II 6.5.2.2 Cauchy's Theorem to Evaluate RHP Roots in 1+T(s)=0 6.5.3 Nyquist Stability Criterion 6.5.4 Application of Nyquist Stability Criterion to Dc‐to‐Dc Converters 6.6 Relative Stability: Gain Margin and Phase Margin 6.7 Chapter Summary Problems Part III Control Schemes and Converter Performance Chapter 7 Feedback Compensation and Closed‐Loop Performance – Voltage Mode Control 7.1 Asymptotic Analysis Method 7.1.1 Concept of Asymptotic Analysis Method 7.1.2 Examples of Asymptotic Analysis Method 7.1.2.1 Procedures for Asymptotic Analysis 7.2 Analysis of Frequency‐Domain Performance in CCM 7.2.1 Audio‐Susceptibility Analysis 7.2.2 Output Impedance Analysis 7.3 Voltage Feedback Compensation and CCM Loop Gain 7.3.1 Problems of Single Integration Function 7.3.2 Voltage Feedback Compensation 7.4 Compensation Design and Closed‐Loop Performance in CCM 7.4.1 Voltage Feedback Compensation and Loop Gain 7.4.2 Feedback Compensation Design Guidelines 7.4.3 Voltage Feedback Compensation and Closed‐Loop Performance 7.4.4 Phase Margin and Closed‐Loop Performance 7.4.5 Compensation Zeros and Speed of Transient Responses 7.4.6 Step Load Response 7.4.7 Non‐Minimum Phase System Case: Boost and Buck/Boost Converters 7.4.7.1 Boost and Buck/Boost Converters 7.4.7.2 Alternative Control Scheme: Current Mode Control 7.5 Consideration of DCM Operation 7.5.1 Review of DCM Converter Dynamics 7.5.2 Control Design Strategy and Converter Performance 7.6 Chapter Summary Reference Problems Chapter 8 Current Mode Control 8.1 Models of Current Mode Control and Chapter Outline 8.1.1 Modeling Peak Current Mode Control 8.1.2 Chapter Outline 8.2 Current Mode Control Basics 8.2.1 Evolution to Peak Current Mode Control 8.2.1.1 Compensation Ramp 8.2.1.2 Peak Current Mode Control 8.2.2 Benefits and Issues of Peak Current Mode Control 8.2.2.1 Benefits of Peak Current Mode Control 8.2.2.2 Issues of Peak Current Mode Control 8.2.3 Average Current Mode Control and Charge Control 8.2.3.1 Average Current Mode Control 8.2.3.2 Charge Control 8.3 Classical Model for Current Mode Control 8.3.1 Classical Small‐Signal Model for Peak Current Mode Control 8.3.2 Classical Small‐Signal Block Diagram of Closed‐Loop Controlled PWM Converters 8.4 Sampling Effects and New s‐Domain Model of Current Mode Control 8.4.1 Origin and Consequences of Sampling Effects 8.4.1.1 Origin of Sampling Effects 8.4.1.2 Consequences of Sampling Effects 8.4.2 Modeling Methodology for Sampling Effects 8.4.3 Feedforward Gains 8.4.4 New s‐Domain Model for Current Mode Control 8.4.5 Two New s‐Domain Models for Current Mode Control 8.5 Expressions for New s‐Domain Model for Current Mode Control 8.5.1 Modified Small‐Signal Model 8.5.2 Modulator Gain Fm* 8.5.3 He(s): s‐Domain Representation of Sampling Effects 8.5.3.1 Step One: Two Different Expressions for Hi(s)=ı^L(s)/v^con 8.5.3.2 Step Two: Identification of Gain Block He(s) 8.5.3.3 Step Three: Approximation of Gain Block He(s) 8.5.4 Feedforward Gains 8.5.4.1 Feedforward Gain kf′ 8.5.4.2 Feedforward Gain kr′ 8.5.4.3 Conversion of Feedforward Gains 8.6 Control Design for Current Mode Control 8.6.1 Composite Power Stage Model 8.6.2 Control‐to‐Output Transfer Function with Current Loop Closed 8.6.2.1 Derivation of Gvci(s) 8.6.2.2 Predictions of Gvci(s) 8.6.3 Control Design Principles 8.6.3.1 Voltage Feedback Compensation 8.6.3.2 Voltage Feedback Compensation for Buck Converter 8.6.3.3 Voltage Feedback Compensation for Boost and Buck/Boost Converters 8.6.3.4 Circuit for Two‐Pole One‐Zero Compensation 8.6.3.5 Current Loop Design Strategy 8.6.4 Step by Step Control Design Procedures 8.6.4.1 Current Loop Design 8.6.4.2 Voltage Feedback Compensation Design 8.7 Step Load Response Analysis 8.7.1 Output Impedance Analysis 8.7.2 Step Load Response Analysis 8.7.2.1 Step Load Response and Compensation Design 8.7.2.2 Generalization of Step Load Response 8.8 Off‐Line Flyback Converter with Optocoupler‐Isolated Current Mode Control 8.8.1 Off‐Line Power Supplies 8.8.2 Current Mode Control for Flyback Converter with Optocoupler‐Isolated Feedback 8.8.2.1 Optocoupler‐Isolated Current Mode Feedback Circuit 8.8.2.2 Small‐Signal Model 8.8.2.3 Optocoupler‐Isolated Feedback Circuit 8.8.2.4 Control Design Procedures 8.9 Chapter Summary References Problems Part IV Dc Power Distribution Systems Chapter 9 Uncoupled Converter and Extra Element Theorem 9.1 Uncoupled Converter 9.1.1 Structure of Dc Power Distribution Systems 9.1.2 Individual Converters in Dc Power Distribution Systems 9.1.3 Uncoupled Converter 9.2 Dynamics and Control of Uncoupled Converters 9.2.1 Uncoupled Buck Converter 9.2.1.1 Power Stage Dynamics 9.2.1.2 Control‐to‐Output Transfer Function with Current Loop Closed 9.2.1.3 Control Design 9.2.2 Uncoupled Boost Converter 9.2.2.1 Power Stage Dynamics 9.2.2.2 Control‐to‐Output Transfer Function with Current Loop Closed 9.2.2.3 Compensation Design 9.2.3 Uncoupled Buck/Boost Converter 9.3 Middlebrook's Extra Element Theorem and Coupled Converters 9.3.1 Middlebrook's Extra Element Theorem 9.3.1.1 Extra Element Theorem 9.3.1.2 Proof of EET 9.3.1.3 EET Application Example 9.3.1.4 Alternative Form of EET 9.3.1.5 Extension of Extra Element Theorem 9.3.2 Performance of Load Coupled Converter 9.3.3 Performance of Source‐Coupled Converter 9.3.4 Performance of Source/Load‐Coupled Converter 9.4 Middlebrook's Feedback Theorem 9.4.1 EET for Feedback‐Controlled Systems 9.4.2 Middlebrook's Feedback Theorem 9.5 Chapter Summary References Problems Chapter 10 Load‐Coupled Converters and Loading Effects 10.1 Load Impedance − Input Impedance of Load Subsystem 10.1.1 Load Impedance Analysis Using Simplified Circuit Model 10.1.2 EET‐Based Load Impedance Analysis 10.1.2.1 Negative Resistance Representation of ZiC(s) 10.2 Stability Analysis of Load‐Coupled Converters 10.2.1 Absolute Stability 10.2.2 Relative Stability 10.3 Loop Gain Analysis of Load‐Coupled Converters 10.3.1 Graphical Analysis and Construction of Loop Gain 10.3.1.1 Loop Gain for Case B 10.3.2 Section Summary 10.4 Other Performance Metrics 10.4.1 Output Impedance 10.4.2 Audio‐Susceptibility 10.4.3 Input Impedance 10.4.4 Transient Response 10.5 Chapter Summary 10.5.1 Load Impedance Analysis 10.5.2 Stability Analysis 10.5.3 Loop Gain Analysis 10.5.4 Other Performance Analysis 10.5.5 Extension to General Load Subsystems References Problems Chapter 11 Source‐Coupled Converters and Input Filter Interaction 11.1 Input Filter‐Coupled Converter and Input Filter Interaction 11.1.1 Input Filter‐Coupled Converter 11.1.2 Transfer Functions of Input Filter‐Coupled Converter 11.1.3 Condition for Stability 11.1.4 Conditions for Minimal Input Filter Interaction 11.1.5 Performance Analysis Under Input Filter Interaction 11.2 Input Filter Interaction Case One–Boost Converter with Voltage Mode Control 11.2.1 Input Impedance Analysis 11.2.1.1 Negative Input Resistance of Regulated Converters 11.2.2 Stability Analysis 11.2.3 Converter Performance Under Input Filter Interaction 11.3 Input Filter Interaction Case Two–Boost Converter with Current Mode Control 11.3.1 Input Impedance Analysis 11.3.2 Converter Performance Metrics 11.3.3 Converter Performance Under Input Filter Interaction 11.3.4 Conditions for Minimal Input Filter Interaction 11.4 Input Filter Interaction Case Three – Buck Converter with Current Mode Control 11.4.1 Input Impedance Analysis 11.4.2 Converter Performance Under Input Filter Interaction 11.5 Chapter Summary 11.5.1 Condition for Stability 11.5.2 Conditions for Minimal Performance Change 11.5.3 Converter Performance Under Input Filter Interaction 11.5.3.1 Case A: Voltage‐Mode Controlled Three Basic Converters 11.5.3.2 Case B: Current‐Mode Controlled Boost and Buck/Boost Converters 11.5.3.3 Case C: Current‐Mode Controlled Buck Converters 11.5.4 Extension to Source‐Coupled Converters References Problems Chapter 12 Design of Dc Power Distribution Systems 12.1 Introduction to Final Chapter: Power System Design Approach 12.1.1 Standalone Functional Unit 12.1.2 Two‐Step Approach to System Design 12.1.3 Two‐Stage Dc Power Distribution System 12.2 Line Filter and Source/Load Impedances of Converters 12.2.1 Load Impedance of Upstream Converter 12.2.2 Source Impedance of Downstream Converter 12.2.3 Impedance Overlap and Impedance Gap 12.2.3.1 Impedance Gap for Stability and Performance of Downstream Converter 12.2.3.2 Impedance Overlap for Performance Programming of Upstream Converter 12.2.3.3 Line Filter and Impedance Overlap/Impedance Gap 12.2.4 Line Filter Design 12.3 Impedance Overlap and Converter Performance 12.3.1 Downstream Converter Performance with Impedance Gap 12.3.2 Upstream Converter Loop Gain with Impedance Overlap 12.3.3 Upstream Converter Input Impedance with Impedance Overlap 12.3.3.1 Input Impedance of Upstream Converter with Current Mode Control 12.3.3.2 Input Impedance of Upstream Converter with Voltage Mode Control 12.3.3.3 Section Summary 12.4 Impedance Overlap and Dc Link Dynamics 12.4.1 Dc Link Impedance Zlink 12.4.1.1 Peaks in Zlink 12.4.2 Transient Response of Dc Link Voltage vlink 12.4.2.1 Qualitative Analysis of vlink 12.4.2.2 Simplified Analysis of vlink 12.5 Design of Multi‐Stage Dc Power Distribution Systems 12.5.1 Design Approach to Multi‐Stage Dc Power Distribution Systems 12.5.2 Line Filter Design 12.5.2.1 Load Impedance 12.5.2.2 Line Filter Design Procedures 12.5.3 Illustrative Example 12.6 Consideration of Parallel Filter‐Converter Modules 12.6.1 Design Outline for Parallel‐Module Systems 12.6.2 Upstream Converter Dynamics in Frequency‐Domain 12.6.3 Dc Link Dynamics 12.6.4 Line Filter Design 12.6.5 Illustrative Example 12.6.5.1 Dominant Filter‐Converter Module 12.6.5.2 Line Filter Design Curve: The ω1−PM1 Curve 12.6.5.3 Creation of Filter Design Curve 12.6.5.4 Accuracy of Design Curve 12.6.5.5 Performance Evaluation and Experimental Validation 12.7 EMI Standards and Line Filter Design 12.7.1 Circuit Properties of Line Filters 12.7.1.1 Current Filtering and Filter Structure 12.7.1.2 Reciprocity and Current Attenuation Function 12.7.2 EMI Standards, Current Attenuation, and Line Filter Design 12.8 Summary of Final Chapter References Problems Appendix A Answers to End‐of‐Chapter Problems Index EULA
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