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Electric machines play a very important role in modern daily life. At homes, electric motors run refrigerators, air conditioners, washers, and many similar appliances. In industry they are used to provide the motion for almost all tools. More than 50% of the generated energy is consumed by electrical motors. Electric generators supply the power consumed by all electric loads. Transformers change the voltage level for economical power transmission and distribution. In addition, most machines have some transformer action as part of their operation. The objective of this course is to understand the fundamental concepts and principles of operation of various types of electrical machines, and to equip the students with basic experimental and modeling skills for handling problems associated with electrical machines.


Objectives and goals in this course are as follows:

  • To learn about three-phase circuits, power, reactive power and phase sequences in three-phase systems.
  • To learn about Magnetic circuits, B-H curves, Faraday's law, hysteresis, hysteresis and eddy current losses, self and mutual inductances.
  • To understand single-phase and three-phase transformers, ideal and practical transformers, equivalent circuits of the transformersefficiency, voltage regulation and power factor in ac circuits equipped with transformers
  • To understand the principles of electromagnetic energy conversion
  • To learn about DC motors and generatorscommutation, problems associated with commutation in real machines and compensating techniques
  • To understand the steady state behaviour of dc motors and generators, magnetization curvetorque-speed characteristics of shunt motors, speed control and dc motor drives.
  • To learn about Induction motors, rotating magnetic fieldssynchronous speed, slip, types of induction motors, induction machines equivalent circuits, developed torque, efficiencypull-out torque, starting torque, and torque-speed characteristicsspeed control in induction machines, slip control, frequency control, and voltage control. Power converters used in induction motor drives.
  • To understand Synchronous generators and motors: Basic principles of synchronous generators and motors, the internal emf, and the magnetization curveequivalent circuits of synchronous motors and generators, synchronous reactance, phasor diagram, the conditions required for paralleling, power and reactive power generation, P-Q plane, synchronous condensersstarting of a synchronous motor, speed control of synchronous motors.