EMI Filter Design, 3rd Edition

EMI Filter Design, 3rd Edition

by Richard Lee Ozenbaugh, Timothy M. Pullen
Released December 2017
Publisher(s): CRC Press
ISBN: 9781351833004

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Book description

With today’s electrical and electronics systems requiring increased levels of performance and reliability, the design of robust EMI filters plays a critical role in EMC compliance. Using a mix of practical methods and theoretical analysis, EMI Filter Design, Third Edition presents both a hands-on and academic approach to the design of EMI filters and the selection of components values. The design approaches covered include matrix methods using table data and the use of Fourier analysis, Laplace transforms, and transfer function realization of LC structures. This edition has been fully revised and updated with additional topics and more streamlined content.

New to the Third Edition

  • Analysis techniques necessary for passive filter realization
  • Matrix method and transfer function analysis approaches for LC filter structure design
  • A more hands-on look at EMI filters and the overall design process

Through this bestselling book’s proven design methodology and practical application of formal techniques, readers learn how to develop simple filter solutions. The authors examine the causes of common- and differential-mode noise and methods of elimination, the source and load impedances for various types of input power interfaces, and the load impedance aspect of EMI filter design. After covering EMI filter structures, topologies, and components, they provide insight into the sizing of components and protection from voltage transients, discuss issues that compromise filter performance, and present a goal for a filter design objective. The text also includes a matrix method for filter design, explains the transfer function method of LC structures and their equivalent polynomials, and gives a circuit design example and analysis techniques. The final chapter presents packaging solutions of EMI filters.

Table of contents

  1. Cover Page
  2. Title Page
  3. Copyright Page
  4. Contents
  5. Preface
  6. Acknowledgments
  7. Authors
  8. Terms and Abbreviations
  9. Organization of the Book
  10. 1 EMI Filters
    1. 1.1 Introduction
    2. 1.2 Technical Challenges
      1. 1.2.1 Controlling Parasitic Uncertainty
    3. 1.3 Types of EMI Filters
      1. 1.3.1 AC Filters
      2. 1.3.2 DC Filters
    4. 1.4 No Such Thing as Black Magic
    5. 1.5 It Is All in the Mathematics
  11. 2 Why Call EMI Filters Black Magic?
    1. 2.1 What Is EMI?
    2. 2.2 Regular Filters versus EMI Filters
    3. 2.3 Specifications: Real or Imagined
    4. 2.4 Inductive Input for the 220-A Test Method
    5. 2.5 400-Hz Filter Compared with the 50- or 60-Hz Filter
  12. 3 Common Mode and Differential Mode: Definition, Cause, and Elimination
    1. 3.1 Definition of Common and Differential Modes
    2. 3.2 Origin of Common-Mode Noise
    3. 3.3 Generation of Common-Mode Noise—Load
    4. 3.4 Elimination of Common-Mode Noise—Line and Load
    5. 3.5 Generation of Differential-Mode Noise?
    6. 3.6 Three-Phase Virtual Ground
  13. 4 EMI Filter Source Impedance of Various Power Lines
    1. 4.1 Skin Effect
    2. 4.2 Applying Transmission Line Concepts and Impedances
    3. 4.3 Applying Transmission Line Impedances to Differential and Common Modes
    4. 4.4 Differences among Power Line Measurements
    5. 4.5 Simple Methods of Measuring AC and DC Power Lines
    6. 4.6 Other Source Impedances
  14. 5 Various AC Load Impedances
    1. 5.1 The Resistive Load
    2. 5.2 Off-Line Regulator with Capacitive Load
    3. 5.3 Off-Line Regulator with an Inductor ahead of the Storage Capacitor
    4. 5.4 Power Factor Correction Circuit
    5. 5.5 Transformer Load
    6. 5.6 UPS Load
  15. 6 DC Circuit—Load and Source
    1. 6.1 Various Source Impedance
    2. 6.2 Switcher Load
    3. 6.3 DC Circuit for EMI Solutions or Recommendations
    4. 6.4 Some Ideas for the Initial Power Supply
    5. 6.5 Other Parts of the System
    6. 6.6 Lossy Components
    7. 6.7 Radiated Emissions
  16. 7 Typical EMI Filters—Pros and Cons
    1. 7.1 The π Filter
    2. 7.2 The T Filter
    3. 7.3 The L Filter
    4. 7.4 The Typical Commercial Filter
    5. 7.5 The Cauer Filter
    6. 7.6 The RC Shunt
    7. 7.7 The Conventional Filters
  17. 8 Filter Components—the Capacitor
    1. 8.1 Capacitor Specifications
    2. 8.2 Capacitor Construction and Self-Resonant Frequency
    3. 8.3 Veeing the Capacitor
    4. 8.4 Margins, Creepage, and Corona—Split Foil for High Voltage
    5. 8.5 Capacitor Design—Wrap-and-Fill Type
  18. 9 Filter Components—the Inductor
    1. 9.1 Inductor Styles and Specifications
    2. 9.2 Core Types
      1. 9.2.1 Power Cores
      2. 9.2.2 Ferrite Cores
      3. 9.2.3 Tape-Wound Toroids
      4. 9.2.4 C-Core Inductors
      5. 9.2.5 Slug Type
      6. 9.2.6 Nanocrystalline Common-Mode Cores
    3. 9.3 High-Current Inductors
    4. 9.4 Inductor Design
    5. 9.5 Converting from Unbalanced to Balanced
  19. 10 Common-Mode Components
    1. 10.1 Capacitor to Ground
    2. 10.2 Virtual Ground
    3. 10.3 Z for Zorro
    4. 10.4 Common-Mode Inductor
    5. 10.5 Common-Mode Calculation
    6. 10.6 Differential Inductance from a Common-Mode Inductor
    7. 10.7 Common-Mode Currents—Do They All Balance?
  20. 11 Transformer’s Addition to the EMI Filter
    1. 11.1 Transformer Advantages
    2. 11.2 Isolation
    3. 11.3 Leakage Current
    4. 11.4 Common Mode
    5. 11.5 Voltage Translation—Step Up or Down
    6. 11.6 Transformer as a Key Component of the EMI Package
    7. 11.7 Skin Effect
    8. 11.8 Review
  21. 12 Electromagnetic Pulse and Voltage Transients
    1. 12.1 Unidirectional versus Bidirectional
    2. 12.2 Three Theories
    3. 12.3 Initial High-Voltage Inductor
    4. 12.4 Arrester Location
    5. 12.5 How to Calculate the Arrester
      1. 12.5.1 Dynamic Resistance
    6. 12.6 The Gas Tube
  22. 13 What Will Compromise the Filter?
    1. 13.1 Specifications—Testing
    2. 13.2 Power Supplies—Either as Source or Load
    3. 13.3 9- and 15-Phase Autotransformers
    4. 13.4 Neutral Wire Not Part of the Common-Mode Inductor
    5. 13.5 Two or More Filters in Cascade—the Unknown Capacitor
    6. 13.6 Poor Filter Grounding
    7. 13.7 “Floating” Filter
    8. 13.8 Unknown Capacitor in the Following Equipment
    9. 13.9 Filter Input and Output Too Close Together
    10. 13.10 Gaskets
  23. 14 Waves as Noise Sources
    1. 14.1 Spike
    2. 14.2 Pulse
    3. 14.4 Power Spectrum—dB µA/MHz
    4. 14.5 MIL-STD-461 Curve
  24. 15 Initial Filter Design Requirements
    1. 15.1 Differential-Mode Design Goals
    2. 15.2 Differential-Mode Filter Input Impedance
    3. 15.3 Differential-Mode Filter Output Impedance
    4. 15.4 Input and Output Impedance for a DC Filter
    5. 15.5 Common-Mode Design Goals
    6. 15.6 Estimation of the Common-Mode Source Impedance
    7. 15.7 Methods of Reducing the Inductor Value due to High Current
  25. 16 Matrices, Transfer Functions, and Insertion Loss
    1. 16.1 Synthesis, Modeling, and Analysis
    2. 16.2 Review of the A Matrix
    3. 16.3 Transfer Functions
    4. 16.4 Review of Matrix Topologies
    5. 16.5 π Filter
    6. 16.6 L Matrix
    7. 16.7 T Filter
    8. 16.8 Cauer or Elliptic Matrix
    9. 16.9 RC Shunt
    10. 16.10 Filter Applications and Thoughts
    11. 16.11 Single-Phase AC Filter
    12. 16.12 Three-Phase Filters
    13. 16.13 Low-Current Wye
    14. 16.14 High-Current Wye
    15. 16.15 Single Insert
    16. 16.16 Low-Current Delta
    17. 16.17 High-Current Delta
    18. 16.18 Telephone and Data Filters
    19. 16.19 Pulse Requirements—How to Pass the Pulse
    20. 16.20 The DC-DC Filter
    21. 16.21 Low-Current Filters
  26. 17 Matrix Applications: A Continuation of Chapter 16
    1. 17.1 Impedance of the Source and Load
    2. 17.2 dB Loss Calculations of a Single π Filter
    3. 17.3 Example of the Calculations for a Single π Filter
    4. 17.4 Double π Filter: Equations and dB Loss
    5. 17.5 Triple π Filter: Equations and dB Loss
  27. 18 Network Analysis of Passive LC Structures
    1. 18.1 Lossless Networks
    2. 18.2 Network Impedances Using Z Parameters
    3. 18.3 Network Admittances Using Y Parameters
    4. 18.4 Transfer Function Analysis—H(jω)
    5. 18.5 Transfer Function Analysis—H(s)
    6. 18.6 Coefficient-Matching Technique
    7. 18.7 EMI Filter Stability
  28. 19 Filter Design Techniques and Design Examples
    1. 19.1 Filter Design Requirements
    2. 19.2 Design Techniques
      1. 19.2.1 Intermediate CE Testing
      2. 19.2.2 Previous Experience—Similar Application
      3. 19.2.3 Analysis, Synthesis, and Simulation
    3. 19.3 Filter Design Summary
      1. 19.3.1 Predesign Objectives
      2. 19.3.2 Define Design Flow
    4. 19.4 EMI Filter Design Example
      1. 19.4.1 Design Process
      2. 19.4.2 Define Peak Harmonic Amplitude
      3. 19.4.3 Define Harmonic Current
      4. 19.4.4 Define Filter −3-dB Pole-Q Frequency for Differential Mode
      5. 19.4.5 Insertion Loss Validation
      6. 19.4.6 Design Example Summary
        1. 19.4.6.1 Define Component Values
        2. 19.4.6.2 Verify Pole-Q Frequency
        3. 19.4.6.3 Define Characteristic Impedance of Filter
        4. 19.4.6.4 Stabilize the Filter
        5. 19.4.6.5 RC Shunt dQ Damping
        6. 19.4.6.6 Series LR dQ Damping
        7. 19.4.6.7 Addition of Common-Mode Choke
        8. 19.4.6.8 Define Common-Mode Pole-Q Frequency
        9. 19.4.6.9 Common-Mode Damping—dQ
        10. 19.4.6.10 Filter Design Summary
    5. 19.5 Four-Pole LC Structure
      1. 19.5.1 Design Approach
  29. 20 Packaging Information
    1. 20.1 Layout
    2. 20.2 Estimated Volume
    3. 20.3 Volume-to-Weight Ratio
    4. 20.4 Potting Compounds
  30. Appendix A: K Values of Different Topologies
  31. Appendix B: LC Passive Filter Design
  32. Appendix C: Conversion Factors
  33. References
  34. Index

Product information

  • Title: EMI Filter Design, 3rd Edition
  • Author(s): Richard Lee Ozenbaugh, Timothy M. Pullen
  • Release date: December 2017
  • Publisher(s): CRC Press
  • ISBN: 9781351833004