Programme Name/s : Electrical Engineering/ Electrical and Electronics Engineering/ Electrical Power System
Programme Code : EE/ EK/ EP
Semester : Fifth
Course Title : A.C. MACHINES PERFORMANCE
Course Code : 315333
I. RATIONALE
AC machines are widely used in various industries and generating stations, while three phase induction motors are work horse of the industries, alternators are used for generating electrical power. This course is designed to enable the diploma students to acquire the knowledge and skills related to operation and maintenance of these AC machines to enhance the employability in the field.
II. INDUSTRY / EMPLOYER EXPECTED OUTCOME
Test the performance of different AC machines in industries.
III. COURSE LEVEL LEARNING OUTCOMES (COS)
Students will be able to achieve & demonstrate the following COs on completion of course based learning
CO1 - Test the performance of three phase induction motor.
CO2 - Control the speed of three phase induction motor using appropriate technique(s).
CO3 - Use single phase induction motor for industrial applications.
CO4 - Test the performance of three phase alternator.
CO5 - Use special purpose electrical machines for industrial applications.
Unit - I Three phase induction motors
1.1 Three phase AC machines: classification.
1.2 Squirrel cage induction motor and slip ring induction motor: constructional details.
1.3 Concept of rotating magnetic field: production of rotating magnetic field (with two and three phases), synchronous speed.
1.4 Squirrel cage induction motor and slip ring induction motor: working principle, comparison.
1.5 Rotor behavior and relations: standstill and running conditions, speed, slip, frequency of induced emf/currents, power factor.
1.6 Slip measurement methods: tachometer, stroboscope, galvanometer.
1.7 Torques: starting, full load and maximum torque & their ratios.
1.8 Torque-slip (T-S) characteristics.
1.9 Squirrel cage induction motor: losses and power stages.
Unit - II Starting and speed control of three phase induction motors
2.1 Necessity of starters for three phase induction motors.
2.2 Primary resistance starter, DOL, auto transformer starter, star delta starter, rotor resistance starter: constructional details and working.
2.3 Soft starters: component details and working.
2.4 Speed control methods: stator voltage control, pole changing, rotor resistance, variable frequency drives (VFD).
Unit - III Single phase induction motors
3.1 Necessity of single-phase induction motor
3.2 Double field revolving theory.
3.3 Self starting techniques : phase splitting, shaded pole, reluctance.
3.4 Types : capacitor start-induction run, capacitor start-capacitor run (two value and single value capacitor), shaded pole: construction, working, torque-slip (T-S) characteristics and applications.
Unit - IV Three phase synchronous machines
4.1 Three phase alternators: constructional details, working principle. Types of alternators and their comparison: turbo alternator and hydro alternator.
4.2 Turbo alternators: advantages of rotating field.
4.3 Relations for speed and frequency.
4.4 Winding: advantages of short pitched winding, relations for pitch factor and distribution factor.
4.5 Excitation system: DC, AC, static.
4.6 E.M.F. equation of alternator.
4.7 Synchronous reactance.
4.8 Armature reaction at various power factors.
4.9 Voltage regulation: direct loading method and synchronous impedance method.
4.10 Synchronization of alternators: definition, necessity and conditions
4.11 Three phase synchronous motor: principle of operation, significance of load angle.
4.12 Synchronous motor for power factor improvement.
Unit - V Special purpose machines
5.1 Universal motor, synchronous reluctance motor, permanent magnet synchronous motors (PMSM), stepper motors.
5.2 Constructional details and working of linear induction motor.
5.3 Single and double sided linear induction motor.
5.4 Applications of linear induction motor.
Micro project
- Collect information in brochures or other means for setting up VVVF drives.
- Collect information/product brochures on different types of alternators.
- Gather information and product brochures on both AC and DC servomotors commonly employed in robotics, CNC machining, conveyor systems, and other motion control applications.
- Collect information and product brochures, for single-phase induction motors and BLDC motor used in ceiling fans.
- Obtain information and product brochures on stepper motors utilized in precision positioning systems, 3D printers, CNC machines, and other motion control applications.
- Visit an industry and collect information/product brochures on three phase induction motors used for lifts, cranes and hoists and prepare reports covering interpretation of technical specification, name of manufacturer, frame size and applications.
- Visit an industry and collect information/product brochures on three phase induction motors used for floor mills, agricultural solar pumps and prepare reports covering interpretation of technical specification, name of manufacturer, frame size and applications.
- Design a model of a three-phase/single-phase induction motor using software such as CAD, CATIA, or SOLIDWORKS to visualize and understand its constructional details.