Inductors and Transformers for Power Electronics

Although they are some of the main components in the design of power electronic converters, the design of inductors and transformers is often still a trial-and-error process due to a long working-in time for these components. Inductors and Transformers for Power Electronics takes the guesswork out of the design and testing of these systems and provides a broad overview of all aspects of design.Inductors and Transformers for Power Electronics uses classical methods and numerical tools such as the finite element method to provide an overview of the basics and technological aspects of design. The authors present a fast approximation method useful in the early design as well as a more detailed analysis. They address design aspects such as the magnetic core and winding, eddy currents, insulation, thermal design, parasitic effects, and measurements. The text contains suggestions for improving designs in specific cases, models of thermal behavior with various levels of complexity, and several loss and thermal measurement techniques.This book offers in a single reference a concise representation of the large body of literature on the subject and supplies tools that designers desperately need to improve the accuracy and performance of their designs by eliminating trial-and-error.

FUNDAMENTALS OF MAGNETIC THEORYBasic Laws of Magnetic TheoryMagnetic MaterialsMagnetic CircuitsReferencesFAST DESIGN APPROACH INCLUDING EDDY CURRENT LOSSESFast Design ApproachExamplesConclusionsAppendix 2.A.1: Core Size Scale Law for Ferrites in Non-Saturated Thermal Limited DesignAppendix 2.A.2: Eddy Current Losses for Wide FrequencyAppendix 2.A.3: MathCAD Example FilesReferencesSOFT MAGNETIC MATERIALSMagnetic Core MaterialsComparison and Applications of the Core Materials in Power ElectronicsLosses in Soft Magnetic MaterialsFerrite Core Losses with Non-Sinusoidal Voltage WaveformsWide Frequency Model of Magnetic Sheets Including Hysteresis EffectsAppendix 3.A: Power and Impedance of Magnetic SheetsReferencesCOIL WINDING AND ELECTRICAL INSULATIONFilling FactorWire LengthPhysical Aspects of BreakdownInsulation Requirements and StandardsThermal Requirements and StandardsMagnetic Component Manufacturing SheetReferencesEDDY CURRENTS IN CONDUCTORSIntroductionBasic ApproximationsLosses in Rectangular ConductorsQuadrature of the Circle Method for Round ConductorsLosses of a Current Carrying Round Conductor in 2-D ApproachLosses of a Round Conductor in a Uniform Transverse AC FieldLow Frequency 2-D Approximation Method for Round ConductorsWide Frequency Method for Calculating Eddy Current Losses in WindingsLosses in Foil WindingsLosses in Planar WindingsAppendix 5.A.1: Eddy Current 1-D Model for Rectangular ConductorsAppendix 5.A.2: Low Frequency 2-D Models for Eddy Current Losses in Round WiresAppendix 5.A.3: Field Factor For InductorsReferencesTHERMAL ASPECTSFast Thermal Design Approach (Level 0 Thermal Design)Single Thermal Resistance Design Approach (Level 1 Thermal Design)Classic Heat Transfer MechanismsThermal Design Utilizing a Resistance NetworkContribution to Heat Transfer Theory of Magnetic ComponentsTransient Heat TransferSummaryAppendix 6.A: Accurate Natural Convection Modeling for Magnetic ComponentsReferencesPARASITIC CAPACITANCES IN MAGNETIC COMPONENTSCapacitance Between Windings: Inter CapacitanceSelf-Capacitance of a Winding: Intra CapacitanceCapacitance Between the Windings and the Magnetic MaterialPractical Approaches for Decreasing the Effects of Parasitic CapacitancesReferencesINDUCTOR DESIGNAir Coils and Related ShapesInductor ShapesTypical Ferrite Inductor ShapesFringing in Wire-Wound Inductors with Magnetic CoresEddy Currents in Inductor WindingsFoil Wound InductorsInductor Types Depending on ApplicationDesign Examples of Different Types of InductorsFringing Coefficients For Gapped-Wire-Wound InductorsAnalitical Modeling of Combined Litz Wire-Full Wire InductorsReferencesTRANSFORMER DESIGNTransformer Design in Power ElectronicsMagnetizing InductanceLeakage InductanceUsing Parallel Wires and Litz WiresInterleaved WindingsSuperimposing Frequency ComponentsSuperimposing ModesReferencesOPTIMAL COPPER/CORE LOSS RATIO IN MAGNETIC COMPONENTSSimplified ApproachLoss Minimization in the General CaseLoss Minimization Without Eddy Current LossesLoss Minimization Including Low-Frequency Eddy Current LossesSummaryExamplesReferencesMEASUREMENTSIntroductionTemperature MeasurementsPower Losses MeasurementsMeasurement of InductancesCore Loss MeasurementsMeasurement of Parasitic CapacitancesCombined Measuring InstrumentsReferencesAPPENDIX A: RMS VALUES OF WAVEFORMSDefinitionsRMS Values of Some Basic WaveformsRMS Values of Common WaveformsAPPENDIX B: MAGNETIC CORE DATAETD Core Data (Economic Transformer Design Core)EE Core DataPlanar EE Core DataER Core DataUU Core DataRing Core Data (Toroid Core)P Core Data (Pot Core)PQ Core DataRM Core DataAPPENDIX C: COPPER WIRES DATARound Wire DataAmerican Wire Gauge DataLitz Wire DataAPPENDIX D: MATHEMATICAL FUNCTIONS ReferencesINDEX

Alex P. M. Van den Bossche received the M.S. and the Ph.D. degrees from the University of Ghent, Belgium in 1980 and 1990 respectively. He has worked there at the Electrical Energy Laboratory Department, EESA. He has been engaged in research and published articles in the field of electrical drives and power electronics concerning various converter types, drives and various aspects of magnetic components and materials. His interests are also in renewable energy conversion. Since 1993, he has been a full professor at the same university. He is a senior member of the IEEE (M’99S’03). Vencislav V. Valchev received the M.Sc. and Ph.D. degrees in electrical engineering from the Technical University of Varna, Bulgaria in 1987 and 2000, respectively. Since 1988 he has been with the Department of Electronics, Technical University of Varna, where he has been a lecturer. His research interests include power electronics, soft switching converters, resonant converters, and magnetic components for power electronics, renewable energy conversion. Dr. Valchev had a cumulated common research period of about four years in the Electric Energy Laboratory research group in Ghent University, Belgium.