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Unit1.
ELECTROMECHANICAL ENERGY CONVERSION: Basic principles of
electromechanical energy conversion. Basic aspects and physical phenomena
involved in energy conversion. Energy balance.
Unit2. DC GENERATORS: Construction, Types of DC generators, emf
equation, lap & wave windings, equalizing connections, armature reaction,
commutation, methods of improving commutations, demagnetizing and cross
magnetizing mmf, interpoles, characteristics, parallel operation.
Rosenberg generator.
Unit3. DC MOTORS: Principle, back emf, types, production of torque,
armature reaction & interpoles, characteristics of shunt, series &
compound motor, DC motor starting. Speed Control of DC Motor: Armature
voltage and field current control methods, Ward Leonard method. Braking,
losses and efficiency, direct & indirect test, Swinburne’s test,
Hopkinsion test, field & retardation test, single-phase series motor.
Unit4. TRANSFORMERS: Construction, types, emf equation. No load and
load conditions. Equivalent circuits, Vector diagrams, OC and SC tests,
Sumpner’s back-to-back test, efficiency. voltage regulation, effect of
frequency, parallel operation, autotransformers, switching currents in
transformers, separation of losses.
Unit5. POLYPHASE TRANSFORMERS: Single unit or bank of single-phase
units, polyphase connections, Open delta and V connections, Phase
conversion: 3 to 6 phase and 3 to 2 phase conversions, Effect of 3-phase
winding connections on harmonics, 3-phase winding transformers, tertiary
winding.
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