ABSTRACT
Induction machines a.c. fed (at frequency f 1) from a single or multiphase power source to a two-phase, respectively, 3+ phase symmetric windings and having a laminated Si –iron stator and rotor core with uniform slots that contain the stator windings and, respectively, on the rotor, a shortcircuited bars or a two (three) phase symmetric winding flowed by a.c. currents at “slip frequency” f 2, while rotor rotates at speed n=(f 1−f 2)/p 1; p 1––number of pole pairs of stator and rotor windings.
The wound rotor is connected through slip rings and brushes to a PWM converter at frequency f 2, while also the cage rotor induction machine works as a generator when f 2<0 (motor for f 2>0).
Applications in industry as motor (mainly) and as generator for wind generators (mainly)––with variable frequency PWM converter interface, construction elements, a.c. distributed windings with their traveling mmf and its harmonics and case studies, pole-count changing and two-phase versions, cage rotor winding, the emf, magnetization and leakage inductance expressions, equivalent circuit of 3 phase induction motor, symmetric steady state (with ideal no load, motor no-load, on- load, stalled rotor, capacitor-excited generator operation modes with case studies), electromagnetic torque characteristics, dual-cage and deep bars rotors, parasitic torques, starting methods and characteristics speed control methods (for the cage and, respectively, wound rotor cases), V/f control, unbalanced voltage fed machine characteristics (one stator phase open, asymmetric rotor, capacitor split-phase induction motor model and symmetrization, linear induction motors with their edge and dynamic end effects, regenerative and virtual loading tests (lab) and preliminary electromagnetic extended methodology via a case study, plus a few proposed problems (with solving hints) and a substantial Summary constitute this major chapter of the book, related to the induction machine the work and race horse (at variable speed) of Industry (with 242 equations and 56 figures).
