Course Details
Subject {L-T-P / C} : EE2001 : Electrical Machines - I { 3-1-0 / 4}
Subject Nature : Theory
Coordinator : Dr. Shubhobrata Rudra
Syllabus
Transformer[15 L]:
A brief recapitulation of the single-phase transformer working principle, different types of tests for determining parameters and specification of a single-phase transformer [2L],
A thorough analysis of the harmonics of a single-phase transformer[1 L]
3-phase transformers – types – phasor groups. Effects of unbalanced loading, generation of harmonics by transformers and their suppression[4L]
3-phase to 2-phase and 3-phase to multiphase transformation[1L].
3-winding transformers – parameters estimation, voltage regulation – applications[2 L].
Parallel operation of transformers[2 L]
Operating principle of single and three-phase autotransformers[2L]
Analysis of harmonics in a three-phase transformer [1L]
DC Machine[5 L]
A brief recapitulation of the working principle of dc machines [2L]
A detailed discussion on the armature reaction and compensation of the same[2 L]
Basic starting and speed control scheme of DC motors. [1L]
Mid-sem Exam
Electro-Mechanical Energy conversion Principle [4 L]:
Forces and Torques in MagneticField Systems, Energy Balance, Energy in the Singly-Excited Magnetic FieldSystems, Determination of Magnetic Force and Torque from Energy [2L]
Determination of Magnetic Force and Torquefrom Conery, Multiply-Excited Magnetic FieldSystems, Forces and Torques in Systems with permanent Magnets [2 L]
Fundamental Theory of Rotating Machines[ 16 L]
EMF of Elementary Alternator, Relation between PolarFlux and Airgap Flux Density [1L]
EMF of elementary Multipolar Alternator, Frequency of Alternation, Factors Affecting the Induced EMF [2 L]
Fourier Analysis of Airgap Flux Density and MMF Distribution [2L]
Armature Windings, Fractional-pitch Windings, and Fractional-slot Windings [2 L]
Induced EMF in Full-pitch Distributed Windings, Fractional-pitch windings, Wave Form of EMF, Nonsinusoidal Field Distribution, Tooth Ripples. Skewing of Slots[ 3 L]
Armature Reaction, MMF of Armature Reaction[2 L]
The rotating Magnetic Field, Effect of Distributed and Fractional-pitch Windings armature Reaction [2 L]
Space Harmonics of MMF. Travelling Waves of MMF Due to TimeHarmonics, Resolving Travelling Waves into Standing Waves[2 L]
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.
- Describing the impact of different armature reactions on a DC machine (both motoring and generating mode).
- Explaining energy conversion process and their modernization, and relevant analysis tools thereof.
- Discussing the different stator and rotor winding designs on their respective emf and MMF waveforms.
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) Determine the cause responsible for the deterioration in a given DC machine performance <br />iv) Cary out the energy flow analysis for a given electromechanical structure. <br />v) Investigate the impacts of different parameters of the electrical machine on its performance <br />vi) Assess the induced emf or generated torque profile for a concerned machine's winding.
Essential Reading
- Alexandar S Langsdorf, Theory of Alternating Current Machinery, McGrawhill
- A.E. Fitzgerald, C. Kingsley, S.D. Umans, Electric Machinery, McGrawhill
Supplementary Reading
- D.C. White and H.H.Woodson, Electromechanical Energy Conversion, John Wiley and Sons
- M. G. Say, The Performance and Design of Alternating Current Machines, CBS publications
Journal and Conferences
- IEEE Transaction on Energy Conversion
- Cigre Annual Conference