Objective
To impart knowledge on constructional details, operating principle and performance of Transformers, DC Machines, 1-phase and 3-phase Induction Machines, 3-phase Synchronous Machines and Fractional Kilowatt Motors.
Syllabus
- Magnetic Circuits and Induction
- Magnetic Circuits
- Ohm’s Law for Magnetic Circuits
- Series and Parallel magnetic circuits
- Core with air gap
- B-H relationship (Magnetization Characteristics)
- Hysteresis with DC and AC excitation
- Hysteresis Loss and Eddy Current Loss
- Faraday’s Law of Electromagnetic Induction, Statically and Dynamically Induced EMF
- Force on Current Carrying Conductor
- Transformer
- Constructional Details, recent trends
- Working principle and EMF equation
- Ideal Transformer
- No load and load Operation
- Operation of Transformer with load
- Equivalent Circuits and Phasor Diagram
- Tests: Polarity Test, Open Circuit test, Short Circuit test and Equivalent Circuit Parameters
- Voltage Regulation
- Losses in a transformer
- Efficiency, condition for maximum efficiency and all day efficiency
- Instrument Transformers: Potential Transformer (PT) and Current Transformer (CT)
- Auto transformer: construction, working principle and Cu saving
- Three phase Transformers
- DC Generator
- Constructional Details and Armature Winding
- Working principle and Commutator Action
- EMF equation
- Method of excitation: separately and self excited, Types of DC Generator
- Characteristics of series, shunt and compound generator
- Losses in DC generators
- Efficiency and Voltage Regulation
- DC Motor
- Working principle and Torque equation
- Back EMF
- Method of excitation, Types of DC motor
- Performance Characteristics of D.C. motors
- Starting of D.C. Motors: 3 point and 4 point starters
- Speed control of D.C. motors: Field Control, Armature Control
- Losses and Efficiency
- Three Phase Induction Machines
- Three Phase Induction Motor
- Constructional Details and Types
- Operating Principle, Rotating Magnetic Field, Synchronous Speed, Slip, Induced EMF, Rotor Current and its frequency, Torque Equation
- Torque-Slip characteristics
- Three Phase Induction Generator
- Working Principle, voltage build up in an Induction Generator
- Power Stages
- Three Phase Synchronous Machines
- Three Phase Synchronous Generator
- Constructional Details, Armature Windings, Types of Rotor, Exciter
- Working Principle
- EMF equation, distribution factor, pitch factor
- Armature Reaction and its effects
- Alternator with load and its phasor diagram
- Three Phase Synchronous Motor
- Principle of operation
- Starting methods
- No load and Load operation, Phasor Diagram
- Effect of Excitation and power factor control
- Fractional Kilowatt Motors
- Single phase Induction Motors: Construction and Characteristics
- Double Field Revolving Theory
- Split phase Induction Motor
- Capacitors start and run motor
- Reluctance start motor
- Alternating Current Series motor and Universal motor
- Special Purpose Machines: Stepper motor, Schrage motor and Servo motor