Course Details
Subject {L-T-P / C} : EE2205 : Electrical Machines { 3-0-0 / 3}
Subject Nature : Theory
Coordinator : Dr. Krishna Roy
Syllabus
Transformer: [10L]
Single Phase Transformer: [2L]
A brief recapitulation of the single-phase transformer working principle, equivalent circuit, phasor diagrams on no load and full load, per-unit representation of transformer parameters, voltage regulation, losses and efficiency, OC and SC test, all day efficiency.
3- phase transformers: [8L]
3-phase transformers – types – phasor groups [2L]
3-phase to 2-phase and 3-phase to multiphase transformation [1L]
3-winding transformers – parameters estimation, voltage regulation – applications [1L]
Parallel operation of 3-phase transformers [2L]
Operating principle of single and three-phase autotransformers [2L]
Fundamental Theory of Rotating Machines: [6L]
EMF of elementary Multipolar Alternator, Frequency of Alternation, Factors Affecting the Induced EMF [2L]
Armature Windings, Fractional-pitch Windings, and Fractional-slot Windings [2L]
Induced EMF and armature MMF in Full-pitch Distributed Windings, Fractional-pitch windings [3L]
MID SEM
Synchronous Machine: [10L]
Alternator types and construction [1L]
Phasor diagram, the concept of synchronous impedance, Potier Triangle, Voltage regulation calculation, measurement of cylindrical rotor machine parameters [5L]
Blondel two reaction theory, load characteristics, measurement of machine parameters [2L]
Motor physical consideration, torque and power relations [2L]
Induction Machines: [10L]
Three phase induction motor:
Construction, the principle of operation [2L]
Equation of mechanical power developed and torque [2L]
No load and Blocked Rotor Test [1L]
Speed control [1L]
Single phase induction motor:
Construction and operation [1L]
Principle of operation - Double revolving field theory [1L]
Starting methods [2L]
Course Objectives
- Providing a knowledge base for transformer operation, both single phase and three phases, as well as studying their operation as a standalone unit and in a group.
- Discussing the different stator and rotor winding designs on their respective emf and MMF waveforms.
- Delivering working knowledge on the synchronous machine performance both for the generating and motoring mode.
- Providing working knowledge on the operation of the slip ring and squirrel cage Induction machine.
Course Outcomes
After attending the course, the students should be able to: <br />i) Analyse the merit of a transformer unit w.r.to different performance index <br />ii) Examine the different operating conditions of three-phase transformers for standalone and parallel operation <br />iii) Assess the induced emf or generated torque profile for a concerned machine's winding. <br />iv) Examine the performance of a synchronous machine for different operating conditions. <br />v) Analyse the nature of power flow from or to a machine connected to an infinite bus. <br />vi) Recommend a suitable starting and speed control method for a specific poly-phase and single phase induction motor.
Essential Reading
- Alexandar S Langsdorf, Theory of Alternating Current Machinery, McGrawhill
- A.E. Fitzgerald, C. Kingsley, S.D. Umans, Electric Machinery, McGrawhill
Supplementary Reading
- M. G. Say, The Performance and Design of Alternating Current Machines, CBS publications
- J. Stephen, Chapman, Electric Machinery Fundamentals, Mc Graw-Hill International , 1991