i. To familiarize the constructional details, the principle of operation, prediction of performance,
the methods of testing the transformers and three phase transformer connections.
ii. To introduce the principles of electromechanical energy conversion in singly and multiply
iii. To study the working principles of electrical machines using the concepts of
electromechanical energy conversion principles and derive expressions for generated voltage and
torque developed in all Electrical Machines.
iv. To study the working principles of DC machines as Generator and Motor, types,
determination of their no-load/load characteristics, starting and methods of speed control of
v. To estimate the various losses taking place in D.C. machines and to study the different testing
methods to arrive at their performance.
UNIT I INTRODUCTION 6
Electrical machine types – Magnetic circuits – Inductance – Statically and Dynamically induced
EMF- Torque – Hysteresis- Core losses - AC operation of magnetic circuits.
UNIT II TRANSFORMERS 10
Construction – principle of operation – equivalent circuit – losses – testing – efficiency and
voltage regulation – auto transformer – three phase connections – parallel operation of
transformers – tap changing.
UNIT III ELECTROMECHANICAL ENERGY CONVERSION 9
Energy in magnetic systems – field energy, coenergy and mechanical force – singly and multiply
UNIT IV BASIC CONCEPTS IN ROTATING MACHINES 9
Generated voltages in ac and dc machines, mmf of distributed windings – magnetic fields in
rotating machines – rotating mmf waves – torque in ac and dc machines.
UNIT V DC MACHINES 11
Construction – EMF and torque – circuit model – armature reaction – commutation – methods of
excitation – characteristics of generators – characteristics of motors – starting and speed control
– testing and efficiency – parallel operation.