The Induction Machines Design Handbook

Developments in power electronics and digital control have made the rugged, low-cost, high-performance induction machine the popular choice of electric generator/motor in many industries. As the induction machine proves to be an efficient power solution for the flexible, distributed systems of the near future, the dynamic worldwide market continues to grow. It is imperative that engineers have a solid grasp of the complex issues of analysis and design associated with these devices. The Induction Machines Design Handbook, Second Edition satisfies this need, providing a comprehensive, self-contained, and up-to-date reference on single- and three-phase induction machines in constant and variable speed applications. Picking up where the first edition left off, this book taps into the authors’ considerable field experience to fortify and summarize the rich existing literature on the subject. Without drastically changing the effective logical structure and content of the original text, this second edition acknowledges notable theoretical and practical developments in the field that have occurred during the eight years since the first publication. It makes corrections and/or improvements to text, formulae, and figures. New material includes: Introduction of more realistic specifications and reworked numerical calculations in some of the examples Changes in terminology Discussion of some novel issues, with illustrative results from recent literature New and updated photos Data on new mild magnetic materials (metglass) An industrial "sinusoidal" two-phase winding Illustrations of finite element method airgap flux density Enhanced presentations of unbalanced voltage and new harmonic-rich voltage supply IM performance Discussion of stator (multiconductor) winding skin effect by finite element method Broad coverage of induction machines includes applications, principles and topologies, and materials, with numerical examples, analysis of transient behavior waveforms and digital simulations, and design sample cases. The authors address both standard and new subjects of induction machines in a way that will be both practically useful and inspirational for the future endeavors of professionals and students alike.

Table of Contents:
Induction Machines: An Introduction Electric energy and induction motors A historical touch Induction machines in applications Construction Aspects and Operation Principles Construction aspects of rotary IMs Construction aspects of linear induction motors Operation principles of IMs Magnetic, Electric, and Insulation Materials for IM Soft magnetic materials Core (magnetic) losses Electrical conductors Insulation materials Induction Machine Windings and Their MMFs The ideal traveling mmf of a.c. windings A primitive single-layer winding A primitive two-layer chorded winding The mmf harmonics for integer q Rules for designing practical a.c. windings Basic fractional q three-phase a.c. windings Basic pole-changing three-phase a.c. windings Two-phase a.c. windings Pole-changing with single-phase supply induction motors Special topics on a.c. windings The mmf of rotor windings The "skewing" mmf concept The Magnetization Curve and Inductance Equivalent airgap to account for slotting Effective stack length The basic magnetization curve The emf in an a.c. winding The magnetization inductance Leakage Inductances and Resistances Leakage fields Differential leakage inductances Rectangular slot leakage inductance/single layer Rectangular slot leakage inductance/two layers Rounded shape slot leakage inductance/two layers Zig-zag airgap leakage inductances End-connection leakage inductance Skewing leakage inductance Rotor bar and end ring equivalent leakage inductance Basic phase resistance The cage rotor resistance Simplified leakage saturation corrections Reducing the rotor to stator Steady-State Equivalent Circuit and Performance Basic steady-state equivalent circuit Classification of operation modes Ideal no-load operation Short-circuit (zero speed) operation No-load motor operation The motor mode of operation Generating to power grid Autonomous induction generator mode The electromagnetic torque Efficiency and power factor Phasor diagrams: Standard and new Alternative equivalent circuits Unbalanced supply voltages One stator phase is open Unbalanced rotor windings One rotor phase is open When voltage varies around rated value When stator voltage have time harmonics Starting and Speed Control Methods Starting of cage-rotor induction motors Starting of wound-rotor induction motors Speed control methods for cage-rotor induction motors Variable frequency methods Speed control methods for wound rotor IMs Skin and On-Load Saturation Effects The skin effect Skin effects by the multilayer approach Skin effect in the end rings via the multilayer approach The double cage behaves like a deep bar cage Leakage flux path saturation-a simplified approach Leakage saturation and skin effects-a comprehensive analytical approach The FEM approach Standardized line-start induction motors Airgap Field Space Harmonics, Parasitic Torques, Radial Forces, and Noise Stator mmf produced airgap flux harmonics Airgap field of a squirrel cage winding Airgap conductance harmonics Leakage saturation influence on airgap conductance Main flux saturation influence on airgap conductance The harmonics-rich airgap flux density The eccentricity influence on airgap magnetic conductance Interactions of mmf (or step) harmonics and airgap magnetic conductance harmonics Parasitic torques Radial forces and electromagnetic noise Losses in Induction Machines Loss classifications Fundamental electromagnetic losses No-load space harmonics (stray no-load) losses in nonskewed IMs Load space harmonics (stray load) losses in nonskewed IMs Flux pulsation (stray) losses in skewed insulated bars Interbar current losses in uninsulated skewed rotor cages No-load rotor skewed uninsulated cage losses Load rotor skewed uninsulated cage losses Rules to reduce full load stray (space harmonics) losses High frequency time harmonics losses Computation of time harmonics conductor losses Time harmonics interbar rotor current losses Computation of time harmonic core losses Thermal Modeling and Cooling Some air cooling methods for IMs Conduction heat transfer Convection heat transfer Heat transfer by radiation Heat transport (thermal transients) in a homogenous body Induction motor thermal transients at stall Intermittent operation Temperature rise (TON) and fall (TOFF) times More realistic thermal equivalent circuits for IMs A detailed thermal equivalent circuit for transients Thermal equivalent circuit identification Thermal analysis through FEM Induction Machine Transients The phase coordinate model The complex variable model Steady state by the complex variable model Equivalent circuits for drives Electrical transients with flux linkages as variables Including magnetic saturation in the space phasor model Saturation and core loss inclusion into the state–space model Reduced order models The sudden short-circuit at terminals Most severe transients (so far) The abc–dq model for PWM inverter fed IMs First order models of IMs for steady-state stability in power systems Multimachine transients Subsynchronous resonance (SSR) The m/Nr actual winding modeling for transients Motor Specifications and Design Principles Typical load shaft torque/speed envelopes Derating due to voltage time harmonics Voltage and frequency variation Specifying induction motors for constant V and f Matching IMs to variable speed/torque loads Design factors Design features The output coefficient design concept The rotor tangential stress design concept IM Design Below 100KW and Constant V and f (Size Your Own IM) Design specifications by example The algorithm Main dimensions of stator core The stator winding Stator slot sizing Rotor slots The magnetization current Resistances and inductances Losses and efficiency Operation characteristics Temperature rise IM Design Above 100KW and Constant V and f (Size Your Own IM) High voltage stator design Low voltage stator design Deep bar cage rotor design Double cage rotor design Wound rotor design IM with wound rotor-performance computation Induction Machine Design for Variable Speed Power and voltage derating Reducing the skin effect in windings Torque pulsations reduction Increasing efficiency Increasing the breakdown torque Wide constant power speed range via voltage management Design for high and super-high speed applications Sample design approach for wide constant power speed range Optimization Design Essential optimization design methods The augmented Lagrangian multiplier method (ALMM) Sequential unconstrained minimization A modified Hooke–Jeeves method Genetic algorithms Three Phase Induction Generators Self-excited induction generator (SEIG) modeling Steady state performance of SEIG The second order slip equation model for steady state Steady state characteristics of SEIG for given speed and capacitor Parameter sensitivity in SEIG analysis Pole changing SEIGs Unbalanced steady state operation of SEIG Transient operation of SEIG SEIG transients with induction motor load Parallel operation of SEIGs The doubly-fed IG connected to the grid Linear Induction Generators Classifications and basic topologies Primary windings Transverse edge effect in double-sided LIM Transverse edge effect in single-sided LIM A technical theory of LIM longitudinal end effects Longitudinal end-effect waves and consequences Secondary power factor and efficiency The optimum goodness factor Linear flat induction actuators (no longitudinal end-effect) Tubular LIAs Short-secondary double-sided LIAs Linear induction motors for urban transportation Transients and control of LIMs Electromagnetic induction launchers Super-High Frequency Models and Behavior of IMs Three high frequency operation impedances The differential impedance Neutral and common mode impedance models The super-high frequency distributed equivalent circuit Bearing currents caused by PWM inverters Ways to reduce PWM inverter bearing currents Testing of Three-Phase IMs Loss segregation tests Efficiency measurements The temperature-rise test via forward short-circuit (FSC) method Parameter estimation tests Noise and vibration measurements: from no-load to load Single-Phase Induction Machines: The Basics Split-phase induction motors Capacitor induction motors The nature of stator-produced airgap field The fundamental mmf and its elliptic wave Forward-backward mmf waves The symmetrical components general model The d-q model The d-q model of star Steinmetz connection Single-Phase Induction Motors: Steady State Steady state performance with open auxiliary winding The split-phase and the capacitor IM: currents and torque Symmetrization conditions Starting torque and current inquires Typical motor characteristic Nonorthogonal stator windings Symmetrization conditions for nonorthogonal windings Mmf space harmonic parasitic torques Torque pulsations Inter-bar rotor currents Voltage harmonics effects The doubly tapped winding capacitor IM Single-Phase IM Transients The d-q model performance in stator coordinates Starting transients The multiple reference model for transients Including the space harmonics Single-Phase Induction Generators Steady state model and performance The d-q model for transients Expanding the operation range with power electronics Single-Phase IM Design Sizing the stator magnetic circuit Sizing the rotor magnetic circuit Sizing the stator windings Resistances and leakage reactances The magnetization reactance Xmm The starting torque and current Steady state performance around rated power Guidelines for a good design Optimization design issues Single-Phase IM Testing Loss segregation in split-phase and capacitor-start IMs The case of closed rotor slots Loss segregation in permanent capacitor IMs Speed (slip) measurements Load testing Complete torque-speed curve measurements Index