Elements of Power Electronics

Philip T. Krein holds the Grainger Endowed Chair in Electric Machinery and Electromechanics as Professor in the Department of Electrical and Computer Engineering at the University of Illinois at Urbana-Champaign. He is a past president of the IEEE Power Electronics Society, and holds twenty-eight U.S. patents, with additional patents pending.

PART I: PRINCIPLES

CHAPTER 1 -- POWER ELECTRONICS AND THE ENERGY REVOLUTION
1.1 The energy basis of electrical engineering
1.2 What is power electronics?
1.3 The need for electrical conversion
1.4 History
» 1.4.1 Rectifiers and the diode
» 1.4.2 Inverters and power transistors
» 1.4.3 Motor drive applications
» 1.4.4 Power supplies and dc-dc conversion
» 1.4.5 Alternative energy processing
» 1.4.6 The energy future: Power electronics as a revolution
» 1.4.7 Summary and future developments
1.5 Goals and methods of electrical conversion
» 1.5.1 The basic objectives
» 1.5.2 The efficiency objective -- the switch
» 1.5.3 The reliability objective -- simplicity and integration
» 1.5.4 Important variables and notation
1.6 Energy analysis of switching power converters
» 1.6.1 Conservation of energy over time
» 1.6.2 Energy flows and action in dc-dc converters
» 1.6.3 Energy flows and action in rectifiers
1.7 Power electronics applications: a universal energy enabler
» 1.7.1 Solar energy architectures
» 1.7.2 Wind energy architectures
» 1.7.3 Tide and wave architectures
» 1.7.4 Electric transportation architectures
1.8 Recap
1.9 Problems
1.10 References

CHAPTER 2 -- SWITCHING CONVERSION AND ANALYSIS
2.1 Introduction
2.2 Combining conventional circuits and switches
» 2.2.1 Organizing a converter to focus on switches
» 2.2.2 Configuration-based analysis
» 2.2.3 The switch matrix as a design tool
2.3 The reality of Kirchhoff's Laws
» 2.3.1 The challenge of switching violations
» 2.3.2 Interconnection of voltage and current sources
» 2.3.3 Short-term and long-term violations
» 2.3.4 Interpretation of average inductor voltage and capacitor current
» 2.3.5 Source conversion
2.4 Switching functions and applications
2.5 Overview of switching devices
» 2.5.1 Real switches
» 2.5.2 The restricted switch
» 2.5.3 Typical devices and their functions
2.6 Methods for diode switch circuits
2.7 Control of converters based on switch action
2.8 Equivalent source methods
2.9 Simulation
2.10 Summary and recap
2.11 Problems
2.12 References


PART II: CONVERTERS AND APPLICATIONS

CHAPTER 3 -- DC-DC CONVERTERS
3.1 The importance of dc-dc conversion
3.2 Why not voltage dividers?
3.3 Linear regulators
» 3.3.1 Regulator circuits
» 3.3.2 Regulation measures
3.4 Direct dc-dc converters and filters
» 3.4.1 The buck converter
» 3.4.2 The boost converter
» 3.4.3 Power filter design
» 3.4.4 Discontinuous modes and critical inductance
3.5 Indirect dc-dc converters
» 3.5.1 The buck-boost converter
» 3.5.2 The boost-buck converter
» 3.5.3 The flyback converter
» 3.5.4 SEPIC, zeta, and other indirect converters
» 3.5.5 Power filters in indirect converters
» 3.5.6 Discontinuous modes in indirect converters
3.6 Forward converters and isolation
» 3.6.1 Basic transformer operation
» 3.6.2 General considerations in forward converters
» 3.6.3 Catch-winding forward converter
» 3.6.4 Forward converters with ac links
» 3.6.5 Boost-derived (current-fed) forward converters
3.7 Bidirectional converters
3.8 Dc-dc converter design issues and examples
» 3.8.1 The high-side switch challenge
» 3.8.2 Limitations of resistive and forward drops
» 3.8.3 Regulation
» 3.8.4 A solar interface converter
» 3.8.5 Electric truck interface converter
» 3.8.6 Telecommunications power supply
3.9 Application discussion
3.10 Recap
3.11 Problems
3.12 References

CHAPTER 4 -- RECTIFIERS AND SWITCHED CAPACITOR CIRCUITS
4.1 Introduction
4.2 Rectifier overview
4.3 The classical rectifier -- operation and analysis
4.4 Phase controlled rectifiers
» 4.4.1 The uncontrolled case.
» 4.4.2 Controlled bridge and midpoint rectifiers
» 4.4.3 The polyphase bridge rectifier
» 4.4.4 Power filtering in rectifiers
» 4.4.5 Discontinuous mode operation
4.5 Active rectifiers
» 4.5.1 Boost rectifier
» 4.5.2 Discontinuous mode flyback and related converters as active rectifiers
» 4.5.3 Polyphase active rectifiers
4.6 Switched-capacitor converters
» 4.6.1 Charge exchange between capacitors
» 4.6.2 Capacitors and switch matrices
» 4.6.3 Doublers and voltage multipliers
4.7 Voltage and current doublers
4.8 Converter design examples
» 4.8.1 Wind-power rectifier
» 4.8.2 Power system control and HVDC
» 4.8.3 Solid-state lighting
» 4.8.4 Vehicle active battery charger
4.9 Application discussion
4.10 Recap
4.11 Problems
4.12 References

CHAPTER 5 -- INVERTERS
5.1 Introduction
5.2 Inverter considerations
5.3 Voltage-sourced inverters and control
5.4 Pulse-width modulation
» 5.4.1 Introduction
» 5.4.2 Creating PWM waveforms
» 5.4.3 Drawbacks of PWM
» 5.4.4 Multi-level PWM
» 5.4.5 Inverter input current under PWM
5.5 Three-phase inverters and space vector modulation
5.6 Current-sourced inverters
5.7 Filters and inverters
5.8 Inverter design examples
» 5.8.1 Solar power interface
» 5.8.2 Uninterruptible power supply
» 5.8.3 Electric vehicle high-performance drive
5.9 Application discussion
5.10 Recap
5.11 Problems
5.12 References


PART III: REAL COMPONENTS AND THEIR EFFECTS

CHAPTER 6 -- REAL SOURCES AND LOADS
6.1 Introduction
6.2 Real loads
» 6.2.1 Quasi-steady loads
» 6.2.2 Transient loads
» 6.2.3 Coping with load variation -- dynamic regulation
6.3 Wire inductance
6.4 Critical values and examples
6.5 Interfaces for real sources
» 6.5.1 Impedance behavior of sources
» 6.5.2 Interfaces for dc sources
» 6.5.3 Interfaces for ac sources
6.6 Source characteristics of batteries
» 6.6.1 Lead-acid cells
» 6.6.2 Nickel batteries
» 6.6.3 Lithium-ion batteries
» 6.6.4 Basis for comparison
6.7 Source characteristics of fuel cells and solar cells
» 6.7.1 Fuel cells
» 6.7.2 Solar cells
6.8 Design examples
» 6.8.1 Wind farm interconnection problems
» 6.8.2 Bypass capacitor benefits
» 6.8.3 Interface for a boost PFC active rectifier
» 6.8.4 Lithium-ion battery charger for a small portable device
6.9 Application discussion
6.10 Recap
6.11 Problems
6.12 References

CHAPTER 7 -- CAPACITORS AND RESISTORS
7.1 Introduction
7.2 Capacitors -- types and equivalent circuits
» 7.2.1 Major types
» 7.2.2 Equivalent circuit
» 7.2.3 Impedance behavior
» 7.2.4 Simple dielectric types and materials
» 7.2.5 Electrolytics
» 7.2.6 Double-layer capacitors
7.3 Effects of ESR
7.4 Effects of ESL
7.5 Wire resistance
» 7.5.1 Wire sizing
» 7.5.2 Traces and busbar
» 7.5.3 Temperature and frequency effects
7.6 Resistors
7.7 Design examples
» 7.7.1 Single-phase inverter energy
» 7.7.2 Paralleling capacitors in a low-voltage dc-dc converter
» 7.7.3 Resistance management in a heat lamp application
7.8 Application discussion
7.9 Recap
7.10 Problems
7.11 References

CHAPTER 8 -- CONCEPTS OF MAGNETICS FOR POWER ELECTRONICS
8.1 Introduction
8.2 Maxwell's equations with magnetic approximations
8.3 Materials and properties
8.4 Magnetic circuits
» 8.4.1 The circuit analogy
» 8.4.2 Inductance
» 8.4.3 Ideal and real transformers
8.5 The hysteresis loop and losses
8.6 Saturation as a design constraint
» 8.6.1 Saturation limits
» 8.6.2 General design considerations
8.7 Design examples
» 8.7.1 Core materials and geometries
» 8.7.2 Additional discussion of transformers
» 8.7.3 Hybrid car boost inductor
» 8.7.4 Building-integrated solar energy converter
» 8.7.5 Isolated converter for small satellite application
8.8 Application discussion
8.9 Recap
8.10 Problems
8.11 References

CHAPTER 9 -- POWER SEMICONDUCTORS IN CONVERTERS
9.1 Introduction
9.2 Switching device states
9.3 Static models
9.4 Switch energy losses and examples
» 9.4.1 General analysis of losses
» 9.4.2 Losses during commutation
» 9.4.3 Examples
9.5 Simple heat transfer models for power semiconductors
9.6 The PN junction as a power device
9.7 PN junction diodes and alternatives
9.8 The thyristor family
9.9 Field-effect transistors
9.10 Insulated-gate bipolar transistors
9.11 Integrated gate-commutated thyristors and combination devices
9.12 Impact of compound and wide bandgap semiconductors
9.13 Snubbers
» 9.13.1 Introduction
» 9.13.2 Lossy turn-off snubbers
» 9.13.3 Lossy turn-on snubbers
» 9.13.4 Combined and lossless snubbers
9.14 Design examples
» 9.14.1 Boost converter for disk drive
» 9.14.2 Loss estimation for electric vehicle inverter
» 9.14.3 Extreme performance devices
9.15 Application discussion
9.16 Recap
9.17 Problems
9.18 References

CHAPTER 10 -- INTERFACING WITH POWER SEMICONDUCTORS
10.1 Introduction
10.2 Gate drives
» 10.2.1 Overview
» 10.2.2 Voltage-controlled gates
» 10.2.3 Pulsed-current gates
» 10.2.4 Gate turn-off thyristors
10.3 Isolation and high-side switching
10.4 P-channel applications and shoot-through
10.5 Sensors for power electronic switches
» 10.5.1 Resistive sensing
» 10.5.2 Integrating sensing functions with the gate drive
» 10.5.3 Noncontact sensing
10.6 Design examples
» 10.6.1 Gate consideration on dc-dc-based battery charger
» 10.6.2 Gate drive impedance requirements
» 10.6.3 Hall sensor accuracy interpretation
10.7 Application discussion
10.8 Recap
10.9 Problems
10.10 References


PART IV: CONTROL ASPECTS

CHAPTER 11 -- OVERVIEW OF FEEDBACK CONTROL FOR CONVERTERS
11.1 Introduction
11.2 The regulation and control problem
» 11.2.1 Introduction
» 11.2.2 Defining the regulation problem
» 11.2.3 The control problem
11.3 Review of feedback control principles
» 11.3.1 Open-loop and closed-loop control
» 11.3.2 Block diagrams
» 11.3.3 System gain and Laplace transforms
» 11.3.4 Transient response and frequency domain
» 11.3.5 Stability
11.4 Converter models for feedback
» 11.4.1 Basic converter dynamics
» 11.4.2 Fast switching models
» 11.4.3 Piecewise-linear models
» 11.4.4 Discrete-time models
11.5 Voltage-mode and current-mode controls for dc-dc converters
» 11.5.1 Voltage-mode control
» 11.5.2 Current-mode control
» 11.5.3 Sensorless current mode and flux controls
» 11.5.4 Large-signal issues in voltage-mode and current-mode control
11.6 Comparator-based controls for rectifier systems
11.7 Proportional and proportional-integral control applications
11.8 Design examples
» 11.8.1 Voltage mode control and performance
» 11.8.2 Feedforward compensation
» 11.8.3 Electric vehicle control setup
11.9 Application discussion
11.10 Recap
11.11 Problems
11.12 References

CHAPTER 12 -- CONTROL MODELING AND DESIGN
12.1 Introduction
12.2 Averaging methods and models
» 12.2.1 Formulation of averaged models
» 12.2.2 Averaged circuit models
12.3 Small-signal analysis and linearization
» 12.3.1 The need for linear models
» 12.3.2 Obtaining linear models
» 12.3.3 Generalizing the process
12.4 Control and control design based on linearization
» 12.4.1 Transfer functions
» 12.4.2 Control design - Introduction
» 12.4.3 Compensation and filtering
» 12.4.4 Compensated feedback examples
» 12.4.5 Challenges for control design
12.5 Design examples
» 12.5.1 Boost converter control example
» 12.5.2 Buck converter design example with current-mode control
» 12.5.3 Buck converter with voltage mode control
12.6 Application discussion
12.7 Recap
12.8 Problems
12.9 References

PART V: ADVANCED TOPICS

CHAPTER 13 -- AC-AC CONVERSION
13.1 Introduction
13.2 Ac regulators and integral cycle control
» 13.2.1 SCR and triac-based ac regulators
» 13.2.2 Integral cycle control
13.3 Frequency matching conditions
13.4 Matrix converters
» 13.4.1 Slow-switching frequency converters: The choice fin - fout
» 13.4.2 Unrestricted frequency converters: The choice fswitch = fin + fout
» 13.4.3 Unifying the direct switching methods: linear phase modulation
13.5 The cycloconverter
13.6 PWM ac-ac conversion
13.7 Dc link converters
13.8 Ac link converters
13.9 Design examples
» 13.9.1 Heater control with triac ac regulator
» 13.9.2 Matrix converter
» 13.9.3 Link converter
13.10 Application discussion
13.11 Recap
13.12 Problems
13.13 References

CHAPTER 14 -- RESONANCE IN CONVERTERS
14.1 Introduction
14.2 Review of resonance
» 14.2.1 Characteristic equations
» 14.2.2 Step function excitation
» 14.2.3 Series resonance
» 14.2.4 Parallel resonance
14.3 Soft switching techniques -- introduction
» 14.3.1 Soft-switching principles
» 14.3.2 Inverter configurations
» 14.3.3 Parallel capacitor as a dc-dc soft switching element
14.4 Soft switching in dc-dc converters
» 14.4.1 Description of quasi-resonance
» 14.4.2 ZCS transistor action
» 14.4.3 ZVS transistor action
14.5 Resonance used for control -- forward converters
14.6 Design examples
» 14.6.1 Limitations of antiresonant filters
» 14.6.2 Creating an ac link for a dc-dc converter
» 14.6.3 Resonant boost converter for solar application
14.7 Application discussion
14.8 Recap
14.9 Problems
14.10 References

CHAPTER 15 -- HYSTERESIS AND GEOMETRIC CONTROL FOR POWER CONVERTERS
15.1 Introduction
15.2 Hysteresis control
» 15.2.1 Definition and basic behavior
» 15.2.2 Hysteresis control in dc-dc converters
» 15.2.3 Hysteresis power factor correction control
» 15.2.4 Inverters
» 15.2.5 Design approaches
15.3 Switching boundary control
» 15.3.1 Behavior near a switching boundary
» 15.3.2 Possible behavior
» 15.3.3 Choosing a switching boundary
15.4 Frequency control in geometric methods
15.5 Design examples
» 15.5.1 Designing hysteresis controllers
» 15.5.2 Switching boundary control combination for battery charging management
» 15.5.3 Boost converter with switching boundary control
15.6 Application discussion
15.7 Recap
15.8 Problems
15.9 References


APPENDIX
A. Trigonometric identities
B. Unit systems
C. Fourier series
D. Three-phase circuits
E. Polyphase graph paper


INDEX